[Alan Roehrich]

If those are production cylinder heads, and have never even had the valve springs changed, that won't be all that is wrong. There probably is not enough clearance between the retainer and the top of the valve guide, either. In cases like that, it is hard to say what has been damaged. If the rockers were not changed to long slot rockers or aftermarket roller rockers, I'd be surprised if the rockers had not hit the rocker studs.