I printed out the post by infomaniac on sealing of copper head gaskets and brought it to my engine builder. I have had the very same problem and it was nice to show that I am not the only one who had this experience.He told me that other customers were aware of the same deal and he designed a fix.He Machines the gasket and installs a composite insert.This seals around the water passages. I will install these on my 572. I am still looking for the right boat to purchase,so the engine assembly wont be completed anytime soon.I can't give anymore details for this reason.If you guys are interested and want more info,mention it in your post and I can give you his number.