Build a cover for your alum. dump box [like a pickup truck shell box cover]. Your alum.sides are about 2 ft. high, so a 5 ft high cover would be appropiate, your box looks close to 8ft wide and about that long, so a 7'x8'x8' box would be more then enough chip space for your f350.
Build the frame out of 1 1/4" alum. tubing and skin it with alum. sheet,put a roof on,cover the front and leave the back open, build the curb side shell wall into full sized double swinging doors so blocks,logs,stump chips can be loaded through that side. 2 guys should have no problem setting it up into place, bolt it to your dump box sides. Line the original dump box sides & front[inside] with 3/4" fir plwood .Line the foor with rubber mat and then cover with 1/8" galvanized steel. Now you won't have to worry about your alum. cracking or getting dinged up,pull your chipper behind and now your ready to make money.
How about a Bandit 150XP 12"chipper with 65-140 h.p. with the wheels,axle and fenders removed and mounted on one side of a 8 ft wide low tandem flat deck trailer with a 36" wide Rayco RG 1645 44hp diesel 4x4 stump grinder mounted along side it. With your F350 pulling this unit you are now a complete tree service , you just gotta leave about 3 ft overhang at the rear of the trailer to load you mini skid steer. LOL.