Well - with the backhoe attachment you might be able to make a half descent shelter. Be sure to "build" so that breezes/wind can blow under and prevent moisture build up.
One piece tarp going to be pain in the butt to cover tractor in the winter with wind blowing,maybe tube shelter might better until you decide on wooden cover.
Yes - I agree Thomas. Something temporary > perhaps made out of rigid plastic piping. Get the tractor adequately covered > get the tarp up and off the paint job.