It is a 427 Side Oiler as far as all the evidence I can find. Cast in Oct 68. I'm still researching where/what the motor came out of.
So we took her home, cleaned her up, threw ~$1,000 into the motor (and some Sunoco Super). Added a little elbow grease and she purrs like a kitten. A very large angry kitten
Now some minor ongoing "project" cleanup items and I think I got a pretty good deal. Thanks for all the help!!