Shovelhead - Its Novak try their web site real good info. Their rebuild kit comes with all the bearings and new rollers and synchronizers. It was $198, the tranny shop wanted 800 plus to rebuild mine. Several of my friends - more skilled with more experience told me it was easy and maybe more important - they did not want to do it, so I decided to give it a try.
The web sight and instructions tell you everything you will need and are pretty good. Only things I needed were some cheapo pullers and a press 3 ton, from Northern tool. My friends said get a bigger one but it did the job and I am pressed for room. Some snap ring pliers are good to have too. Thats about it. I would not call it really easy myself - but it was not bad either. I had a harder time getting the tranny back in by myself than anything else.
I think the other guys might be right, my truck is kind of a beater and I am getting more in it then its worth, but as long as I can still pay for gas I will keep it.Mainly I like working on my stuff and trying to learn about it, not to mention - I cant afford the pro's help very often. In my area, the trans shops were telling me the 420's are getting pretty hard to come by. I dont know if thats right or if they were trying to stick me. I rode a shovel for 25 years, a Sturgis 81 - it was an excellent machine!! Good luck, Tom.