So I'm looking at my latest y block acquisition here. Its a marine y block. Has the side draft intake set up. Ports drilled in the timing cover water castings. Big square oil pan. There are no numbers to be found on the block. I've looked at all the tell tale places to look and nothing. I wire brushed the same areas to see if someone has taken then off but it's all original casting. No grind or file marks at all. Funny. Any opinions out there??