Common crack areas on 440

Hey guys-
Just picked up a 440 over the weekend.
I was told she had a bunch of antifreeze in the oil. It's a 1977, out of a small motorhome (has 452 heads)70K miles on it, seems like it has never been apart yet.
I got the heads and intake off, bores look good. Oil definately has water in it, but all spins over just fine. Are there common areas that these crack? Only time I have ever seen cracked 440 blocks was in the main webbing area, never near any water. Might possibly be the heads, I didn't rip them apart yet, but visually they look OK.
Thanks for any ideas.

Look in the valley above the lifters...

Look real closely at the cylinder walls. Some of those blocks have pretty thin walls and I have seen split walls. Head cracks are very common as well.

MB