I bought a console for my 1970 GTO in 1982. The guy I bought it from coated it with mineral oil and swore it was the best thing for vinyl. To this day, that console is as soft as the day it was made, and the dash is all cracked to heck. I wish I had believed the guy and started doing my dash with mineral oil. The console on the GTO has the same pattern and finish as the dash of my 69 Firebird.
You can get mineral oil at the drug store. It's in the laxatives section.
