1: Drive shaft. I would use one from a 1641 or 1440
2: Motor plate and spacers. Again one from a 1641 or 1440
3: Muffler. Again one from a 1641 or 1440
4: Pump adapter to adapt the early style pump to the later drive shaft. Parts by Jeff
5: Cooling duct work. I used some roll plastic that I got from a race car supply.
Pics are from a 1210 that I did years ago, pretty much same as what you want to do.