No valve adjustment?

If you find a good cam lobe with a bad lifter, that would be a first for me. As Dan mentioned, you should be able to pull the cam if you remove the grille, front bumper, lower valance, and radiator. With the mismatch of parts on your engine, I think I'd make sure the conversion was done properly too. Recheck the push rod length on a good lifter to see if it's in specs and compare it to the bad one.