I wouldn't risk driving any car with 20-30 year old tires. That is just me. These tires are 42 years old so a huge difference between 30 and 42 years.... You get bonus points for original tires so that is why they are on the car, plus I love the Tiger Paws and they look cool:) I have 30 year old 19" NOS Goodyear bias plys on one of my 935's but they are just for display. Would never consider driving on them either and they are unfortunately not reproduced at this time so I run a 16" wheel on the back when I race. Forget the value of the car it is just too dangerous.
Based on the window sticker for the sister car shown in Jerry's book on page 117 (it is optioned exactly the same as my car) I possibly should have YJ rallys and not XT wheels. Not 100% sure but every other option on our cars is identical and they only ordered two COPO cars. So I am looking for a proper set and if I don't find some soon will go with some TT style wheels, grey centers with machine lip.
I appreciate the input. It helped my thought process.