Audi quattro inner structure

[quattro84dk]

Hello
Im new here so hope it is posted correctly
I have recently bought a 84 Audi quattro WR that has been standing still for a lot of years. Its a LHD since im from Denmark.
I have started taking it apart carefully since it has alot of rust in the A-pillers from bottom windshieldlevel and down to the panels, front also has some in the engine bay mostly in the lower sections of front inner fender and also in the bottom of the wheelarches where it connects to the front "chassislegs?"
My question right now is which donorcars can I use for spareparts? Also which outerparts do actually work? My bootlid is good, but hood is bad and doors are bottomless. Anything here I need to be aware of concerning production years or so?

Greetings
quattro84dk