As the title states I'm trying to ID my motor. I was told by the previous owner that he installed a crate 350 due to the original motor being blown. I have searched the entire front of the block and cant find any castings. Only thing I could find was tag with the following information:
CLV-1
68188
I've searched google and cant find any relation to these numbers. Any other suggestions on identifying what kind of motor it is?

 

Back of the block has casting #
Best it is going to give you is engine ci
Any codes on the front block pad will be meaningless if engine rebuilt ( unless GM crate engine )
Re-builders usually stamp their own ID codes for warranty purposes

 

I dont have that lip on mine by the valve covers like you show in your picture. Everywhere I've searched says to look there.

 

Yes you do. It's not near the valve cover, it's behind the head at the back of the block.

 

If block is a late model one , will say 5.0L or 5.7L in position shown below and block casting # will be in same position on opposite side

 

also dont forget, every PO has installed a 350 in the 3rd gen your about to buy, infact, its possible there isnt a single 3rd gen for sale with a 305 in it!