I found a 1983 C30 searria Sierra Classic heavy haul pickup with only 147,000 miles on it sitting at a farm no longer in use. It has a heavy 6.2 diesel, with an after market Banks side winder turbo and a special 10 speed manual transmission! The back window on this standard squally was removed and a sleeper was installed right behind the cab. 2- 36 gallon saddle tanks. And a gooseneck tow package was installed. Along with special ordered aluminum bud rims. It is going to be fun to restore and drive.