As mentioned by JimTN. Canadian heads were aluminum for 24 bolt 59a. Cheater heads in the roundy-round crowd. After 50-70 yrs I wouldn't assume anything is original to the line. 21 bolt fords went till mid/late 38. Then 24 bolt. 81a, 99, 59 etc...
If you had a 37/early 38 block you would have a 21 bolt heads with center head water outlets that can bolt to a 36. Only issue is there is no lower block water pumps into the block. You can however put a 37 block in a 36 and block off a few holes and run head water pumps.
Just a stupid thought.
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