Kitty Cat Snowmobiles

I was wondering how hard of a job it is to do the crank seals on 92 kitty. Has anyone had a go at this? just looking for any pointers or stuff to watch out for. I have a problem with my kitty only running with the choke on, i have replaced most the parts in the carb. and still no luck. i tried spraying carb cleaner on the recoil side and my rpm's increased, indicating weak seals so i have read on this site. over 100 psi on compression check.Any input would be awesome! Thanks in Advance!!

I'm doing this to a 92 kitty as we speak.
It's really not a big deal if you have the right parts for the job and a service manual.