Noises from your motor can make you nuts!
I myself will tear it down till i find the problem soon as it starts! So i see how you feel.
First before the headers i would just replace the gaskets... And listen to her, have a friend do the same see what he thinks, also a good old school mech can pin point a sound a mile away! You should have a few in your town.
Could just be cam/lifter time and thats easy!
or if shes still running good leave it till you next rebuild But if your nuts like me let me know and well take it from there

jeff
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"GTO? Good Times Only!!!" "Get Tools Out!!!"
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