what frame do i need for a crewcab shortbed chevy

i am looking at a quad cab and shortbed box for a chevy. its a 80's cab. what frame do i need to get

A longbed crew cab frame and shorten it or build your own.

^Diddo get a parts truck and use the frame off it if its staright or jig it and build ur own like mentioned.

Where are you located? I have a 78 crew cab dually for sale cheap! No motor or trans but the frame is good.