A 1952 GMC would have probably had a 228 or 248 engine. 292's didn't come out until the mid-1960's or so. The linkage in your picture looks like it's from a 216 or 235 from the mid-1950's. There's not going to be any kind of direct-fit linkage available, so you're probably on your own getting the gas pedal and the carburetor married up. It might be a good idea to look at a 292 in its original application and try to adapt the linkage to the truck you're running. The best approach would probably be to use an aftermarket gas pedal with a cable and fabricate a bellcrank to move the throttle quadrant on the carb, using the pivot hole in the intake manifold as a starting point.
Jerry

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