Pretty sure all 2.02's came with screw in studs for high performance applications too.
I think the first 2.02s with screw in studs started in 1969. I know some of the early 2.02's were press in, they might have all been.
Edit: Hmmm, after thinking about it, seems like some of the earlier 2.02s were screw in but didn't have the milled flat for the rocker stud. The studs were screwed in, but you had to use two rocker arm nuts on the stud to turn them in and out.
Well, I guess that pretty well demonstrates how much I know about screw in rocker studs, so I guess I'll stop embarrassing myself now and let someone who really knows straighten this all out.
(you older guys will get the reference)