Ok guys, sorry for ANOTHER post but here is some more info. On the back of the engine behind the bellhousing there are these numbers... 871 it looks like, very close together, then below that and to the side a bit it says 886. Now that is on passenger side..
I took the valve cover off of passenger head and here are the numbers at the front... 3890462
D207 (below)
And then near the middle in between the front and second cylinder there is a number 13, in the middle of the head it says GM 21...

Those are all the numbers and markings on the block and I can't find anything else. Again, sorry for all the posts and I really appreciate all the help you guys are giving me. I don't know much about the numbers and decoding the blocks and you older guys have been doing it for years so I came to you first.