Are the rocker arms "riding" on the centers of the valve stems? If not you definitly have a pushrod mis match.

If you cant tell just by looking. try poping a few off (maybe all 4 corners of the engine)and use some white out on the valve stems to see where they are at. Put it back together and crank it, then see what it looks like. Should be across the center 1/3rd of the stem.

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