I think you should remove that D662 from the Kubota tractor and use it to repower a Cub. Maybe a nice 982.... another 982, not the one you already have.
Sell what's left of the Kubota as a roller parts machine. And forget about the XT.
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Keep the Kubota all together instead of taking it apart and use it. It's a better tractor. Won't cost you anything to keep it.
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If you feel an urge to spend a handful of cash, you can send me the Kubota and $500 in cash and I'll send you a 104. You will have spent less, and gotten a tractor that is made better and will last longer than the XT..... and I will be happy, happy, happy!