Ok so I've built three of these so far, and when I posted the first one several of you wanted plans. I've made some modifications from the original in that I added quite a bit of extra pitch to the roof. Looks better, and drains better.
It's 8" out of square horizontally, 4" out of plum, and has an 1 1/2" drop in the center of the ridge line.
This is not a tractor, though it could easily be made into one if you so desired. The wheels and sub frame you see is how I move it when I deliver it.