Technical Needing help identifying this Ford flat head V8

I have obtained a 1938 Ford Flat head 24 stud V8 I think, and I am trying to identify what I have. It is either a 81A or a 59A

It has a front mount helmet distributor but the stamp on the head says the letter A

 

59A was built after 1945, so if the engine was made in 38, it ain’t one.

 

I thought the 24 stud started in 1939, ……(but a Wikipedia search says late 1938)

Perhaps photos would help ? ? ?
(how often have we said this)

or maybe try looking here
http://www.vanpeltsales.com/FH_web/flathead_specs-85to100mid.htm

.

 

I also have a '38 24 stud and also have the A on the head, that's just what they had on there, I don't think it means anything really. As stated above, the 59A series didn't start until after the war so it isn't that.

 

Heads and distributors are easy to switch. To know what kind of block you have, look for the casting number on top of the bellhousing.

 

The '38 was 24 stud, but the older fords are 221 cu in. Better to find a 239, plus you can bore and stroke them for pretty good power.