If you are trying to order a clutch before you split it you are wasting your time. When I was at the dealer we could call down to engineering with the serial number and they could tell us just about anything, but NOT what clutch was in it. Yes you can get lucky, but unless you are picking it up locally where you would have no shipping involved you need to split it and see what you have. I made up a cheat sheet for myself that will help you get the correct one the first time. Your date code appears to be June '65, but all model numbers starting with "G" are large row crop tractors so you need to clean up the stamping better and recheck it.