[bigblockv6]

GMC never ceased to be a division of GM, what you're saying makes no sense at all. Despite the talk of 67 being the same as Chevrolet that is not true either. 1967-68 even though were a new body style were still being produced in the same manor 66 and earlier trucks were other than Suburbans. Light duty trucks were still manufactured in GMC's Pontiac Michigan plant and at other GM assembly lines on separate assembly lines from Chevrolet. GMC's exclusive colors like Terrace Blue and Palomino tan also carried over and so did rear leaf spring rear suspension. Now 1969 became a transitional year, no more GMC exclusive exterior colors, Dana 44 axles were dropped in favor of Corporate 12 bolt axles, coil spring rear suspension became available, the availability of the V6 was down to just the 305E and that lasted till March of 1969. 1970 came no light duty pickups were manufactured at GMC's Pontiac Michigan plant, just at GM assembly plants, the V6 was gone but continued on in medium and heavy duty trucks and of course silver was no longer used on tailgate letters. It may have not been official but by then GMC light duty trucks were looked at as being rebadged Chevrolet trucks though they still had some considerable differences over Chevrolet. Now 1973 GMC were nothing but Chevrolet trucks, they came off the same assembly lines and all that was different were emblems that fit in the same holes a different grille insert that screwed into the same holes, only the tailgate was different because it had "GMC" stamped on it. It wasn't unusual for a GMC truck to be delivered to a dealer with a Chevrolet tailgate at that point.