I just can't get my valve covers to stop leaking. I have a 383 with stock heads... it leaks pretty on the passenger back outboard side and runs down the bell housing. I 've tried different gaskets, sealants...just when I think I have it licked it comes back. Looking at the top of the head, the gasket surface is very narrow and a little rounded... almost a ridge. Should'nt this area be a little wider and flat? It looks like it could be a bad casting...any how it leaks pretty good and short of getting a new head I don't know what to do. Any ideas? Thanks