OK - since you won't be tractoring for a while...
It's time to make sure you have your documentation straight.
Cancelled checks.
Purchase agreements
Service records
Phone records - who, when, subject of call, promises made, actual results
Dates in shop
Hours run between shop visits
All other records of communication
Any other pertinent info
Put all this cool documentation together to get ready for the BBB arbitration or small claims suit. Hopefully neither of these things happen, but it sure looks like it's heading that direction. Might as well be prepared with documentation on your end because NH and the dealer will have none of it.
Then, google a handy little term "Demand Letter". A well-written Demand Letter sent by certified mail can take this from 'polite what-if conversation' to 'hey boss, check this out - this guy's pi$$ed'. Include all the information you just put together with the letter and send a copy to the NH Regional Manager and the owner of the dealership. It's time to start getting what you paid for.
It amazes me that vehicle and tractor dealers aren't willing to do a trade when these things happen with new machines. I'd think it would be in their best interests in the long run. Turn the angry customer into a happy customer. Fix the tractor without the pressure of getting it back to an already-ticked-off customer. Sure, the original machine will have a few hours on it, but that's the cost of doing business. Maybe no profit left after the fixes, but that's the way it goes. Instead, they end up with bad publicity and maybe facing civil suits or BBB arbitration which certainly publicizes the problem and costs time and money.
Good luck with whatever you choose to do. You can still get what you want by being polite and professional.
Real quick - I did what I suggest above with a VW automobile I bought new in 2000. Total POS. At the BBB arbitration hearing, I presented all my written and physical evidence right down to a sample of the leaking clutch fluid from the floor of my garage. The VW Regional Rep was speechless. When the arbiter left the room, he asked me what he could do. I told him - you had your chance to be nice - now we're going to see what the arbiter decides. The Regional Rep offered me a new car to drive until the decision was made. No thanks - I'd rather ride my bike than drive one of your cars. :laughing:
VW bought that car back from me. Very satisfying to finally get it resolved. Still didn't 'win' as it cost me some money in the long run, but I was pleased to be done with that brand and their dealership.