^^^Right!^^^ Can drive inner wheel up onto a block to change the outer only when they are lug-mounted
Its internal thread goes over the stud in the hub, holding the inner dual. Then the outer dual is held by a nut over the external threads.
I carry a 10- or 12-ton bottle jack, a jack stand, miscellaneous blocks, lug wrench, and recently a 120VAC impact. Lug wrench is a cross-rim (4-way) from NAPA made for trucks, about 24" arms. I also suggest something thin like a 1/4" aluminum plate to rest the jack on. Sometimes a jack won't fit under the axle if it's on a 2x-something block.