383 engine noise

Check around headers/manifolds for carbon deposits, if not most likely a lifter problem
It looks really clean around where the exhaust manifolds bolt to heads, but like I said I am running the stock manifolds with gaskets, I heard that you don't need gaskets when running stock exhaust manifolds on a big block. Also when I had the heads reconditioned the machine shop milled the heads 6 (six) thousands.The Block was left alone.