When it comes to customizing classic trucks, one of the tasks at hand is cleaning up the stock body lines while gaining functionality in the process. For '73-87 Chevrolet and GMC truck owners, the problem just got a lot easier thanks to One-Piece Products of Whittier, California, and the introduction of their one-piece window kits. Installing a one-piece window kit on a truck is one of those rare projects that seems like it would be a lot of work because of the dramatic changes it produces, but in reality, it's quite simple.
We thought a good way to really put the one-piece window kit to the test would be to buy a beat-up old door from the junkyard and see if there were any problems. Typically, most C-10s seem to end up with a pair of those big, ugly West Coast mirrors strapped to the door, ultimately ending up with torn-out bolt holes and warped to boot. Our door was no exception. We didn't worry about the holes, but we did address the area below the window scrapers, which needs to be straight. The best way to check it is to look at it as if you were trying to find a good two-by-four. The bodyline must run parallel with the window glass. The next step is to make sure the area isn't flimsy. One-Piece Products includes a steel reinforcement bar to stiffen the area where the vent window track/brace is removed. With the vent window assembly removed, there are three screw holes that need to be filled. You can use the three plugs included in the kit, or, as we are doing with our '75 C-10 SS496 project, weld the holes up.
From here, our next step was to remove the front and rear window tracks, then make the necessary modifications explained in the directions. For the rear window channel guide, the kit includes a bracket with a built-in 4-inch extension that moves the channel closer to the door latch. In front, because the vent window assembly has been eliminated, the kit includes a new window channel to accommodate the new, longer, tempered one-piece door glass. Also included is a template indicating where the new holes need to be drilled, with the largest being 1 1/4-inch. Before we could permanently install the one-piece window, we went through a series of minor steps illustrated here with photos and captions. All in all, the installation went pretty smoothly, and when we tackled the other door, thanks to familiarity, it only took us about half as long to complete.