I was given a 77 C20 that was used by a crop dusting company in nearby Warden, WA. I plan on doing minor restoring and maintenance to get it running again. It has sat since 99. I removed 5, 55gal trash bags of garbage and a pool table, out of the bed. It has the 292 6cyl engine. I soaked the cylinders with Marvel Oil, and the engine will turn by hand (spark plugs out , of course). The bed is nearly all rusted out. Might have been the crop dusting chemicals he dealt with.