In the parts department, you might get a good deal on body panels and door/interior parts. Especially early electric window switches or dash pads. Most people don't want to mess with big stuff, they are gold to the right market.
Would this be for pickups? or vans? There are plenty of very good condition junkyard vehicles around here for that kind of stuff. At auto repair shop auctions, even new, it usually doesn't sell, and gets tossed into the trash dumpster.