Robert,
I own an automotive shop and coming from my own experience, if 5k is the agreed upon price, 5k is what you pay UNLESS they get it pre-approved by you BEFORE beginning the extra work. I understand you have a good relationship with the dealer and want to keep it that way, however that dealer is there to serve YOU, not the other way around. Coming from a legal standpoint all you have to do is pay the 5k and take the tractor with you. There is absolutely nothing that dealer can do about it except get kranky and refuse service to you, which if they know anything at all about running a business they would know they HAVE to keep the customer happy to stay in business. It all comes down to the fact that it's the dealer's fault. They made the mistake. If they are a loyal dealer they will admit that.
I own an automotive shop and coming from my own experience, if 5k is the agreed upon price, 5k is what you pay UNLESS they get it pre-approved by you BEFORE beginning the extra work. I understand you have a good relationship with the dealer and want to keep it that way, however that dealer is there to serve YOU, not the other way around. Coming from a legal standpoint all you have to do is pay the 5k and take the tractor with you. There is absolutely nothing that dealer can do about it except get kranky and refuse service to you, which if they know anything at all about running a business they would know they HAVE to keep the customer happy to stay in business. It all comes down to the fact that it's the dealer's fault. They made the mistake. If they are a loyal dealer they will admit that.