Undy, the only problem I can foresee with the U joint is the needle bearings getting pounded flat over time. I know if you run a driveshaft at 0 degree you can have that problem so I'm thinking with the limited motion the needles might not rotate enough to keep them round. If this is the case I might play with machining 4 bronze bushings to replace the needles.
DAVENET, thank you sir!
snowcatt, thank you as well, I must say I like the 4.27 gears, with the 2.3L and automatic I haven't been in a situation yet where I wish I still had the stock gearing. with a 200 i6 I'd say go for the 4.27's for sure.
Northcoast, it made this cat a new machine, much more versatile now which is a great thing for a private owner trying to justify owning a snowcat of any kind becasue we all know here, they are not cheap! altho the look on some peoples faces when you mention you own a groomer/snow cat is priceless at times haha.