I ran the motor today and got it warmed up enough to fill the radiator. I drained all the oil again and left the drain plug out. So far. the radiator is full and there is no water leaking out the oil pan or outside of the block. Lucky me!!

 

Check the filler cap inside too. If the oil is not milky, you're good to go I think. Sounds like you got a super deal, and very lucky to be a running engine too! This will surely make the cost of restoration much more agreeable!

 

I'll probably run oil through it a few times until it comes out clean. Just looked up the block number, it's 3970014. Definatley a 350. Nastysz28 say 70-73 la built camaro. Could be 2 or 4 bolt and 200 or 300 horse. Even an ugly squirrel gets a nut every now and then!!