Thanks for all the responses.
I'll go the stop drill and epoxy route first and see what happens. I suppose that Devcon Epoxy Steel is available at parts outlets. I'll try to put a little V in the groove with the die grinder and plug the stop holes with steel rod.
Brian, your vacuum idea sounds good. Even though I don't think it's possible to get the inside of the block clean enough for the epoxy to stick, having it in there should make the patch stronger. And if it still squirts a little I'll have more meat for the stop-leak to stick to.
