If you truly want to find the cancer that is eating away at your hot rod, have it acid-dipped. That’s exactly what happened with our 1968 Pontiac GTO (aka Project Payback). It was a high desert car, but that didn’t make it immune to common GM A-body trouble areas like the lower windshield channel. There seems to be a design flaw with the front and rear windshield that held moisture (or rainwater specifically). Modern vehicles channel rainwater skillfully away from anywhere on the body it might collect. However, the A-body liked collecting water at the bottom of the front and rear windshield, where it oxidized and ate away at the metal.
First, we removed the rear glass to install the roll bar, which is when we discovered that we’d have to replace the lower channel to put the glass back in (check out the build thread for images of that). And then when we removed the rest of the glass and acid-dipped the shell, we found a lot more rust had eaten away the front lower windshield channel as well as the cowl area. We searched high and wide, and Auto Metal Direct (AMD) is one of the only suppliers of this particular piece (P/N 465-3468), which fits all ’68-’72 A-bodies from the GTO to the Skylark, Chevelle, Monte Carlo, and Cutlass.
We were very thankful that the skilled crew at Innovation Performance Technologies could walk us through this process, and provide the right leadership on the build. Unlike the rest of the body and metalwork, replacing this piece is fairly straightforward and doesn’t require a lot of finesse. The lower windshield channel, dash, and cowl come together like a jigsaw puzzle. While there is a proper order of operations, you don’t need to make a million adjustments to get things straight. Once you have punched out the welds on the cowl, the lower windshield channel is unbolted from the dash and away it goes. The new one lays right in and is bolted to the dash, then welded to the cowl pieces. In our case, those were rusted too and needed to be replaced. We’ll have a future story on replacing that.
These discoveries are the ugly side of restoring a vehicle. If you just get it running and throw it together, you never know what sort of problems are lurking under the surface (literally). This was our original plan, until we decided to elevate the build quality once the car got to Innovation. We have had a number of these sort of surprises on this project lately, but when it’s done – this car is going to be rock solid and provide decades of enjoyment.