@WOLFGANG, No conversion required, the rear drums and front disc are standard VW 4 lug (x130) . the PO used Empi bolt pattern adapters that are 1" thick aluminum rings to convert to 5 lug. These would push track width out by 2 inches overall. no way the rears would fit the classic fenders. I would have to buy all new parts to convert to 5x130 or 5x205 to use any P wheels plus buying the wheels. Current thought, just get 10slots with 4 bolt pattern or like you, find 914 2.0L Fuchs, can't really decide which I like better.
First goal, actually get the car working (with what I have) with minimal invested. Then start the customize. If someone had a set of VW wheels lying around to use as "rollers" that would be helpful with determining clearance for what tire I can use when I get the body bolted.
I should probably mount the fr & rr suspensions before worrying about wheels. one step at a time. ( also painting/reconditioning parts as I go. New bearings, grease, seals, etc. )