how do i tell if i have screw in or pressed in rocker studs?
with all this mass quantity of information you gave us here…look and see.
If the heads are stock, you probably have pressed in. If the heads have been modified for performance, using after market springs, a long duration cam, and the engine is buzzing 9 grand, you probably have screw in studs.
More information = more help
The screw in ones have flanks on them that fit a wrench.