Technical cant idenitify my 48 Merc flathead engine

TAG ON BLOCK and the heads also

 

Well the cylinders are 080 over, the mains are 030 over and the rods are 020 over. That's a rebuilding tag.

 

HEADS ?

 

Put a magnet to the head. I think that casting is aluminum.

Cliff Ramsdell

 

Steel cast

 

Ford Barn has some info here:

https://www.fordbarn.com/forum/showthread.php?p=975582

Here's the pertinent info from that thread:
Canada used 3 heads for '46-8, there's a C59A that is about like our 59a, presumably 1946 use, and for '47-8 a C7RA-A iron head exactly equivalent to USA 59AB, and the C7RA-B aluminum one with slightly higher compression.