I Bought Too Much Truck

I think your concerns about the size of the F250 vs the F150 are somewhat overblown. The extra width of the F250 is all in the mirrors- the bodies are exactly the same width. (well, the F250 is a tenth of an inch wider) The F150 is listed with the standard mirrors, and towing that big trailer you'll want towing mirrors. That will put you at the same width as the F250. The F250 is only two inches higher than the F150, so not a huge difference there. Doors are the same as well. I daily drive a newer F150 at work, and I don't find that it's really any easier to park than my older F250. The big difference is that the newer truck has a much tighter turning radius, but older Fords are notoriously piggy when it come to turning. Towing a 9K 37' trailer, I think you'll be much happier with the F250.