[cub108]

hello all,
1. I have a 108 and 109 with a 12 horse in it. will the QA42A work on both tractors?
2. I saw it before and cannot find it for the life of me an article for rebuilding the snowthrower. Can someone send me a link for checking the u-joints, setting the tension on the chain, the fluid that is installed in the gear box, and finally the small sprocket end play, how to take it apart and the correct play it is suppose to have Will I need to shim the sprocket shaft due to play? How do I check the bearings for the small sprocket?
thanks for your help.