Thanks to Art, Dennis, and Rich.
I know we should have O-ringed the block, but we obtained some special ARP studs that are 220,000 psi material (regular ones are 180,000, I think) and the are SUPPOSED to keep the head from lifting under boost...
We'll see. If we have cylinder sealing problems at the head/block interface, , we'll take it off and do it right...
Thanks for all the good info, Rich!