There's another current thread about someone buying a JD 110 and he needs the 3PH parts too. I can't recall the thread title, or I'd link it.
I know our esteemed TBNer, AKFish, posted a response, so you could look for recent posts by him (use the TBN search function).
Anyway, it seem the 3PH parts for the new 4x20 series tractors will work.