Transmission speedometer drive gear for 52 panhead

[lrcormier]

After purchasing a new 11 tooth speedometer drive unit to replace the 13 tooth one I had it became obvious to me when I tried to install it that something was wrong. I will be using a original speedometer on this recently resurrected project. I purchased this transmission around 83 and don't know the full history of it but I did have a HD dealership rebuild it back then so it should be ready to run. Based on attached photos I've determined this is a OCT 46 transmission so likely first used on a 47, but the 13 tooth speedo drive unit with the transmissions 4 tooth gear drive means it was likely used on 63-69 bike at one time. My question is if I purchase a new 7 tooth speedometer drive gear (35635-36) can I swap it with the one currently in the transmission? I understand these are pressed on so do I need to have my machinist remove old and install new or is it possible to do in my garage without a press?

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