Most likely one doesn't exist. Cub Cadet/ MTD produces very few repair manuals. But you can try calling Cub Cadet on that XT1-LT42 KH mower.
The Kohler engine does have a repair manual but the Tuff Torq TL200 transaxle doesn't.
So most of us just use the part list drawing as guide to repairing these jigsaw puzzles.