The tools needed to change a tire are not all that bulky or complicated, really. I would suggest maybe borrowing a jack etc. from someone at home sometime and seeing if you have the strength to change a tire. The lug nuts on the Ford E-series are torqued to 140 foot pounds, which is not too hard to undo with something like a 24" breaker bar and maybe a pipe extension. The wheels are a bit on the heavy side, but nothing like 19" or especially 22.5" wheels and tires.
Do make sure you chock the diagonally opposite wheel. Do take care to not get yourself underneath the RV when it is supported only by the jack. (I sometimes need to be partly underneath to jack up the rear axle, but the wheels are attached to the hub at that point sufficiently that, should the jack slip, they would keep the motorhome from crushing my body. The lug nuts should only be broken free before jacking, not removed to any great extent.)