not sure about your situation but Pontiac stock heads won't take high lift cams, which sounds like what you have,, RAI & III style, 068 cam etc yes, but something like a RAII or IV, no, the factory used different heads with different springs, your push rods should be bent too if this is the case, Crane makes what they call Blueprint cams which are indentical to the factory, the 068 or 744 cams are great cams
So what cam then was in the 1969 350 H.O. automatic .. the 068 ? I have the cast 48 heads and matching intake and carb,, and also the ram air exhaust manifolds.