For most vintage pickup trucks with a cab-mounted gas tank located behind the seat, there’s not typically a lot of room left over for any storage; in fact, there really isn’t any room. Removing the tank frees up enough space to add all kinds of things behind the seat, but it’s usually not real pretty. The tanks were usually left in a semi-raw state, that is, most trucks didn’t get a full upholstery job around the tank, not to mention the surrounding cab sheetmetal. Once removed, the resulting space once occupied by the gas tank needs to be addressed if your plans consist of making the interior of your truck nice and finished.
In past editorials, I’ve waxed philosophically about how projects get hijacked by all those projects that you didn’t expect to tackle at first glance; for me, this is one of those projects. Not that there’s anything wrong with a little extra work. In fact, I went back and forth about how far I wanted to take this little project and at the end of the day it turned out to be more work than I first expected, but it also turned out much nicer than it ever would have if I’d had taken the lazy way out.
When I started looking for locations to mount the Holley Dominator ECU in the cab of my ’68 C10, it became quickly apparent that there was a lack of room behind the dash. Under the seat there was a similar situation, since I had already mounted a pair of Kicker subwoofers as well as a DX 600.5 amp and the PXi50.2 iPod controller. That left the space created behind the seat when I relocated the gas tank as the perfect spot, provided the wiring harness would reach. As it turned out, if I routed the main bundle through the trans pan and up the back of the engine instead of out the top of the firewall, not only would it be less of an eyesore, but it would stretch from the ECU to all the components in the engine compartment with room to spare. Solves that dilemma!
But I couldn’t simply bolt the ECU to the floor and call it a day, could I? Nope. And that’s where the sidetrack begins, because not only did I need to mount the Dominator ECU, I had a pair of 12-inch Kicker Comp RT enclosures that I wanted to add to the existing Kicker stereo system I installed a year or so ago. With the stock gas tank out of the way, it now meant I could add those as well.
The first step in getting these components in place was to fabricate a nice base that could be mounted to the truck’s cab since the floor where the original tank sat was uneven. A 60x5-inch piece of ¾-inch pine was used to mount atop the high points on the cab’s floor, attaching with a handful of ¼-20 fasteners. Then the ECU was centered and bolted in place, followed by the two subs.
With that sorted, it was time to dress up the backside of the cab. It’s basically one big piece of sheetmetal, so first I added a bit of Dynamat to help deaden the tin can effect before creating three templates to cover the back side of the cab. Once satisfied with the fit of the templates, I transferred their dimensions to a piece of 1⁄16-inch, 4x8-foot plastic wall panel that I picked up from the local hardware store. This stuff is nice and flexible and is impervious to moisture, mold, mildew, and looks great covered in carpet, which I also sourced from the local do-it-all box store. A quick coat of spray-on adhesive to both surfaces and I had three panels covered in carpet, held in place on the back of the cab thanks to a dozen or so Velcro strips.
For a day’s worth of work and about $30 in material, I’m pretty happy with my mini-upholstery job. It gave me a nice platform to mount the engine’s ECU as well as some added tunes and finished off the back of the cab nicely. While I would have been happier spending the time wiring the truck and getting it that much closer to the road, I knew at some point I would have to tackle this project, so it just made sense to handle it now rather than later. And I’m glad I did, as it’s one less thing to worry about later!