I am not sure I understand your question. Is the engine in the car or do you want to put one in? If not I would suggest a 153 inch GM engine or a 181 GM industrial engine. My first suggesting would be to keep it original. Attached is a picture of a 181 industrial engine with 153 manifolds...
Good luck. If I remember correctly the late B's used the V8 starter switch might might be easier to find. Also check with someone that rebuilds starters, they may have a core with switch parts.
Charlie Stephens
Kevin,
Welcome to the site. You posted in a section intended for questions to the editors about the site. You would get better responses if you posted here: https://www.fordbarn.com/forum/forumdisplay.php?f=4 Ignore the fact that it says V8, they let the banger guys in. Don’t worry about...