Can you tell whether a 1954 distributor from a 239 is a 13 or 14 tooth gear without removing it from the engine? Also, same question as the whether the drive connecting to the oil pump is slotted or hex: Can you tell without removing the distributor? (I'm interested in purchasing a spare I came across.)

I didn't know if it was an EBU vs. EBV thing. My car has the EBU castings on the engine, and the engine is original to the car and not rebuilt, AS FAR AS I KNOW. Thanks for any help you can provide.