This is a parts list with pictures to convert. Through some horsetrading, I ended up with a parts 1450 w/o engine so I had to purchase the engine parts separately. Since the 129 engine is solid mounted, you may not need item (50) but I installed it anyway. I just modified my original shaft to work with the new set up. It's been a few years but I think I shortened it besides drilling new holes. You will need the spirol pins that Matt listed above for the driveshaft. My parts manual does not show that.
Parts List
1) Shaft, Drive #IH-140079-C1
2) Arm, Coupling #748-3001
3) Disc, Flexible Coupling #722-3000
4) Flange, Drive Shaft #703-0204 (Superseded to 903-0204)
5) Coupler, Drive Shaft #719-3027 (Superseded to 919-3027)
7) Bushing, Self Aligning Ball #741-3004 (Superseded to 941-3004)
8) Fan, Cooling #IH-547749-R1 (Superseded to IH-547749-R2)
50) Ball, 5/8 Cr Stl #723-3022