[amc49]

Put something soft on the top and tap it back in a bit. They get crooked and then lock up and force used lifting it out locks it to seize up. They have to come out dead straight or they do that and if force used to make the bottom out of round you need a new one. They are different thicknesses too to set valve clearances.

 

[amc49]

I see what looks like some cam bearing surface denting on the half journal to the left too, if so remove the highs from the dents or you will tear up that next and new head time if unlucky. Maybe somebody was prying with a tool using that bore.......don't.