None that I know of that I would recommend
Lots that I would not
Knuckle imparred following the dirctions of the mentally imparred is not a good idea
Download your mower parts diagram
Look for all the bolts that hold down the drive
Usually 3 or 4 in the side around the axel and a brace plate between the two drives
Take some photos as you go
Use a paint pen / marker pen to mark the various control rod and their levers so you can put them back together in the right places
Most have only 1 position
In order
1) remove the belt
2) jack up mower & put jack stands under it, lower the mower & remove the rear wheel
3) remove the linkages ( the jack stands will always be in the way no matter where you put them , Murphy's Law )
4) remove the brace plate between the trannys usually 2 to 4 bolts
5) put a jack under the trans ( they are heavier than you think )
6) remove the mounting bolts 3 to 4 bolts
7) remove the tranny.
Most will have to be tilted then then dropped down as the axel usually goes through a hole in the side and most will foul on the other one before the axel clears the hole , thus the need to jack up the mower