This was my dad’s truck, leased since new by Mountain Bell, whom turned it over to a dealership that sold it to dad in 1998, at 92K miles. By 2018, it only had 102K original miles, and required a rebuilt carb to make it out of the driveway. I have no idea if the carburetor they matched was original to the truck (actually doubt it based on a few ‘tells’). For the next few thousand miles all was well, then it became a mess all over again, sluggish, vapor locking, bucking, etc. I’m fully prepared to explore every fuel related system, sensor, heat valve, linkage, etc, but need 100% certainty that the carburetor I’m working with is correct to the factory LT9 motor, and all related emissions gadgets. Then I can move forward knowing I’m diagnosing a fuel system that has the correctly configured carburetor relevant to the checklist. As it sits now, there appear to be discrepancies related to linkages, and fittings, that lead me to suspect at some point an incorrect QJet variant was swapped into the truck.