I have a '77 blazer(Cheyenne) with a bent frame. I bought a '78 blazer(silverado) parts truck about 8 months ago and now I've been told that the frame on silverados are 6" shorter than cheyennes. Is this true?
They were probably thinking of a short bed silverado pickup. The only major difference in K5 frames was from '76 to '77 (may want to double check that) for the rear foot well, where it changes from bed floor to cab is in a slightly different place. Silverado and Cheyenne are simply trim packages.