The Dash & Interior Rebuild of a 1953 GMC Panel Truck

In this process, we took an existing 1953 GMC Panel Truck and completely restored the body. Below, you can see a diagram of the colors we used for the truck thanks to Planet Color. Below that, you can look through a gallery of images taken during the restoration process from start to finish.

Firewall Insulator

The firewall insulator was prepositioned in the truck and holes marked on the back side that we would need. After cutting and punching we mounted the insulator leaving the driver’s side loose so that we could run the wiring behind it in a one-inch “track” we cut half wy through the insulating material. This will allow the firewall insulator to lay against the firewall.

Cowl Insulation

Before we did anything under the dash, we installed the cowl insulation befoe there were any obstructions that would get in the way-wiring, guages, wipere motor, heat/AC distribution plenum, etc.

Steering Column

The steering column was one of the parts saved from the Caprice. We wanted a GM column and it was in great shape except for the funkey steering wheel--we found a good replacement 1993 wheel at the Delta Auto Wrecking yard. The steering column went in after the insulator was installed because it partially rests on the bottom edge of the insulator. The S-10 steering column and brake turned out to be a simple solution. The lenght of the S-10 firewall to dash support bracket is a perfect fit in the 1953 dash. We had to do a little bending and cutting on the end of the bracket to make way for the diameter of the Caprice column. To make the steering column match up to the S-10 bracket, we had to move the upper mounting “T” bracket by grinding the welds off. We used one inch stand-offs between the steering colum “T” and the lower edge of the dash. For the brake pedal, we use a stock swing pedal from a 1986 Chevy half-ton truck.

Parking Brake

Since we had removed the old floor mounted parking pedal and its related hardware, we needed a replacement. We found the perfect solution in a 1968-72 Chey truck parking brake assembly. It hangs down along the driver’s side cowl as though it ws planned by the factory. The firewall to dash length was perfect.


The fuse block and related electronics were mounted in the new seat pan under the driver’s seat to reduce the “rats nest” under the dash. Of the 60 some wires that leave the fuse block, only those that were needed for the gauges, steering column and the Old Air Products Hurrican airconditioning unit and accessories were brought up behind the firewall insulator. The rest of the wiring goes back to the tail lights and fuel tank, the engine or the headlights.

To make things compact under the drivers seat, we mounted the fuse block, relays and miscelanous compter relays and sensors to a wood base with enough slack in the wire harness umbelical to allow it to slide out for service.

Here is how we “branched” the wiring tree:

The bundle of dash wires comes out of the front of the seat pan box, under the floor pan and up through the original e-brake hole in the driver floor and then up along the toe board and behind the firewall (we cut a “channel” in the firewall insulation to accomodate the wiring.) We will build a foot rest “box” to mount on to the toe board to protect the wiring.

A second branch of wires--headlights, signal lights, brake switch and horn--was routed along the inner front fender to the front of the truck.

From the Caprice computer, a third branch of wires (mainly the composed of the Painless ignition wiring harness) exits the seat pan and crosses over to the passenger side and ties into the engine wiring harness and sensors.

The fourth branch of wires leaves the rear of the seat pan through a small hole and feeds the fuel pump, fuel gauge, and tail lights.

Engine Wiring. For the engine computer we used the Painless TBI wiring harness and for the general body wiring we used a universal street rod wiring harnes that we found on EBay.

Dash Instruments

Haneline’s new Three-N-One Elelctric dash instruments were the perfect choice to replace the stock GMC mechanical gauges. The new gauges include the Speedo, Fuel and Volt in one set five-inch and Tach, Temperaguwe and Oil in the other cluster. The three-N-One gauges were desiged for custom applicaations with a 120 MPH speedo, LCD odometer, fuel and volt plus matching tach with oil, and temperature for custom installaltion. The gauges offer a clean design, flexibility and state-of-the-art mechanics. The two-gauge set included all the sending units, trim rings and brackets and the installation was straight forward and simple. The Haneline gauges have their own wire harness that we pluged into the main body harness. We needed a transmision indicator and found the perfect fit with a Dakota Digital transmission gear indicator that also included turnsignals. Installation was easy lwtih its onw harness and sending unit.has its own harness.

Windshield Wiper

The old vacuum wiper was still woking after all these years, but we decided to replace it with a 12 volt unit made by Newport Engineering. It was a direct replacement installation and took about an hour to pull the old one out and install the new unit. We opted for the intermittent switch which fits up under the dash in the same location as the old “switch” and it uses the same dash knob so it all looks original.

HVAC Systems

The AcoustiTRUCK will be on the road and to make the interior comfortable, we wanted airconditioning. Uncontrolled heat in older cars is always an issue, and factory air conditioning for a truck in 1953 was unheard of. Old Air Products of Fortworth, Texas offered the custom solution with an under-dash unit that is formed to fit the bottom lip of the dash--it looks “factory.”
The 1947-54 Chevy/GMC Truck Hurricane A/C Heat/Defrost System comes with the Deluxe Plenum and Cable Operated controls for Defrost & Heater Functions, and was easy to install. The Hurracane Heat Cool & Defrost Unit attaches to the firewall using original heater mounting holes. A/C and Heater fitting pass through the factory blower motor hole with a custom rubber grommet. The compact design retains cowl vent and a majority of the glove box.
The custom molded plenum fits along bottom edge of the dash for switching and louvers. The plenum can be painted or covered with upholstry to match the interior of the truck.
The condenser assembly includes an aluminum “Super Kool Condenser” receiver/drier, mounting brackets and custom tubes for either driver or passenger side mounted compresor. We adding the optional trinary switch upgrade and additional 14” electric condenser fan to increase airflow across condenser to maximize the A/C system performance.
We worked with the folks at Old Air Products on the radiator needs. We had been looking at rather pricey custom radiator units and when they recommened tht we try a Griffin radiator that came out of a 1969 Mustang. It fit the stock 1953 Chevy/GMC radiator support perfectly with a little vertical room to spare. All we had to do was relocate the mounting holes and make a “U” shaped pipe for the lower radiator hose.

Uniquely GM Parts

For those special trim parts that are unique to GMC and Chevrolet trucks, we turned to The Filling Station and Steve and Jerry Kassis who we have known for more than 30 years--we were Sacramento neighbors at one point in the mid-1970s when we were just getting started.

We learned rather quickly at the start of this project, that there are times when it is often more economical to replace a part with a quality reporduction than to rebuild or restore it. A visit to your local chrome shop will shock you into reality--expecially when it comes to low grade potmetal parts that need to be refinished. Bumbers were another shocker as well--the cost of new straight bumpers was the same or less than re-chroming and the quality is better.

Rubber and Glass

As with any vehicle this age, the rubber window and door seals are dried and cracked or all together missing. We ordered everything we needed from the Filling Station to completely refurbish the truck--window glass and rubber as well as door seals. Kendell McSparren of McSparren Auto Glass of Stockton did the installation and saved us lot of time and guess work. He has had quite a number of these old trucks in his shop over the years.

Dash Display

The AcoustiTruck has all of the twenty-first century bells and whistles including a 7” Valor Multimedia Center with navigation, bluetooth, AM/FM/CD a/DVD and rear view camera—all hidden away under the stock dash facia. We installed a set of glove box hinges on both ends of the center dash grill that folds down to reveal the Valor system. Once the dash grill is lowered, the Valor screen slides out into a full upright position for easy viewing.

The rear view camera is located in a false tailpipe at the rear of the car.

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