Thanks for the help!

[cheburashka]

Great advice given here. It's even better when you actually listen to what's said, instead of trying to look for the answer you're after. So after replacing the head, JB welding the block, and putting on a brand new new manifold and riser, my 3.0 Mercruiser is running. I haven't put it in the water yet, but it goes great on the muffs and has no sign of water in the oil or leaking out the side of the block. I'm a happy guy.

Thanks for all your help!