I'm planning on putting new seals and bearings in the sprocket hub of my Bombardier SkiDozer this afternoon. I don't know if the Bombi is the same. If Boggie reads your post, he could likely help. One thing you'll need if your situation is like mine is a special tool for removing and/or tightening the lock nut and outer seal carrier. They've got four slots around their perimeter for turning them on or off the axle tube (the tool will have to fit inside the sprocket hub). If you've got an owners manual, you could see the order of parts. If not, carefully label the parts as you remove them and notice how they were positioned on the axle tube. I made my "special" tool by finding a pipe the same outside diameter as the locking nut and welding four lengths of 1/4 inch key stock on the outside of that pipe to match the spacing on the locking nut.
Good luck.