Ha!
Long story short.......
This is my '07 JD X300 lawn tractor, bought new at the end of '07. Got 400 hrs. on it and it runs like, well, a Deere.
However.......
Rear transaxle finally burned up. I guess wheelie poppin', hilly yard mowin', and 150 lb. core aerator pullin' finally did that transaxle in.
Debated whether to rebuild the old, get a new stock replacement, or upgrade.
Studied the online JD parts catalogs and came to a decision.
For a few hunnert more bucks over stock, I upgraded the transaxle from stock to the next beefier in the Tuff-Torq catalog. Went from a K46 to a K58.
The new transaxle is found in the upper level X300 line and has an actual JD-part number. As a result, it's pretty much a direct bolt in replacement.
Anyway, the old wheels wouldn't work with the new rearend (old rear had 3/4" axles, new has 1" axles), so I got bigger wheels and new tyres (went from 8" wheels to 10"), which necessitated new baby moons in back. Those are unobtainium NOS JD baby moons, which I fell into a literal giveaway on eBay. Like $24 +shipping.
I did have to modify one K46 part needed for the install. Drive pulley and fan are stock JD parts, but from different X-series tractors. Kept the original drive belt and all the control rods fell into their respective stock locations.
Took like three hours to swap old out for new. No biggie.
The original front 6" wheels looked funny when I put the Sodbuster on the ground, and the mower deck was tilted to the front (resulting in limited rear deck adjustment capability), so I got a set of used 8"ers offa eBay to set things more level. Those front baby moons are the original rear set, polished to a high lustre with some Turtle Wax Chrome Polish.
Anywho, the Sodbuster runs mucho better now. Lots of pep and no more freewheelin' down slopes. And the howly/grindy rearend noises are in the past.
Sodbuster needs detailed, tho.
Mark one more busted piece of stuff in my garage as 'fixed'.
p.s.: Short story not so short.