From what I'm understanding, your best option would be to call them,
very early in the morning. That way they can be 100% sure that the tranny you have is the R151F. Does it have the removable rubber plug in the bottom of the bellhousing? And they should be able to search out in the scrap pile for the gear you need. And if you call them, be patient when trying to get through to them. They are very busy, and generally short handed up front, because they sometimes pull the salesmen to help fill orders in the back.
to Marlin!!
