Flathead Ford V8 engine ID numbers
For the most part Ford flatheads do not have engine ID casting numbers like many late model engines.
The 1932-37 21 stud engines and the early 38-42 24 stud engines have no markings.
The 45-48 engines are marked in various ways "59" "59A" "59C" on the cast in block bellhousing. Even these marks do not guarantee what you have any more than head part numbers cast into the heads. There were replacement "59" blocks sold with the 3 1/16 bore as replacements for the earlier 85HP engines rather than the 3 3/16" bore indicated by the "59".
The same pretty much applies to the 49-53 engines.
There is so much interchangeability of parts that you could be the owner of a full race flathead with a Mercury 4" crank offset ground to 4 1/4 and overbored 100 thousands using with modified iron heads so you would never know until you opened it up and used a measuring stick on it!!