AntiFreeze in the Oil Pan

I have a 1968 Camaro that has a freshly rebuilt 327. The engine has approximately 6000 miles on the rebuild. The car sat for two months while the body was restored and painted. At the paint shop the engine started up with no problems. No unusual sounds or smoke. When I got the car home (in a trailer) I tried to start her and I got one turn from the starter. I thought the battery was dead and replaced it with a new one. No change so I tested the starter. The starter tested good so I checked the oil for the unthinkable. Out came at least a quart or more of clean antifreeze before the oil started to drain. I'm assuming that I have a blown head gasket and probably a craked block. At a minimum I hydrolocked the engine, right? Is there a way to determine if I cracked the block before I buy the new engine? I have seen small amounts of antifreeze in the oil before, but this was a lot, so much so that the oil was floated out of the seal and was leaking from the flywheel. The radiator is also low enough that I can't see fluid. I need guidance before I start spending money.