Rocker Studs on 1969 Z.28 Heads

[Prackman]

186 Heads - Were all the rocker studs 'pressed in' during the 1969 302 production year or did the Flint engine plant switch to a 'screw in' style stud, with push rod guides,  at some point during the production year?

[1968 Z28]

No screw in studs prior to 1970.  Screw-in rocker studs with steel rocker guide plates started in 1970 on the Corvette LT1 and Camaro Z28 350 ci engine.

[Prackman]

Jerry - thanks for clarifying