First make sure it's not full of body rot, then get everything back to good stock condition...........bushings, dampers, tires breaks and any engine/drive train issues. Once you have it mechnically sound and looking decent then start with some bolt on's. It sounds like you want to keep a period look. Find some nice wheels with the proper vintage look 13" jelly beans, Libres , Mini Lites etc. Then put on some anti sway bars. After that maybe some Recaro seats.........think bolt on items and keep the stock parts............there that should keep you busy for the next 3 years.

Tom