If history repeats itself, you might be waiting until this winter. The rates seem to be best in the winter then get progressively worse as we roll into summer.
On my current tractor (2210) I went with the 0% for 24 months.
I ordered a new tractor (3520) and locked in a 2.9 % for 36 months. The small amount of interest I'll pay is worth it to me right now, and I can always pay down the principal early. And yes, I agree the large payment is definitely worth it, but you have to be set up financially to swing it.
I'd suggest you start making payments on your future tractor right now. Set up a separate account and put aside whatever payment you can afford. This winter or whenever the rates are more appealing, you will have a nice little downpayment and you can walk into a similar monthly payment. This will save you a great deal of money in interest.
If you aren't stuck on green, then look at blue. They seem to have better financing in the winter. As for me, I'm sticking with green. Good luck !