440 head noise. Perpetual problems. Problem solved

so I took the valve cover off and ran it and the sound is there but the aluminum valve cover must be amplifieing it some how. I have researched it and people describe the sound of a bad lifter as a tapping but this is not the sound I have. The sound I have is a rattling. So my question is if it's a bad lifter how can I tell which ones are bad? I have put pressure on all of them and none can be pushed down at all. There also doesn't seem to be any thing broken. I'm about to start tearing the top end off this pos and any advice would be greatly appreciated.