With regard to removing the rear wheel, Cox's FAQ answer may help:
"How do I get the front and rear wheels off my mower?
Front Wheel
Remove hub cap using multi grips, jack up machine and remove the stub axle nut using 30mm or 1 3/16� socket spanner or remove the steering tie rod bolt and split pin or circlip on the stub axle and allow the wheel assembly to drop out.
Rear Wheel
Using a 24mm or 15/16 socket spanner, remove the rear axle nut and washer. Spray the axle both sides of the wheel hub with CRC or similar. Replace the nut and leave flush with the end of the axle. With the mower still on the ground use a suitable solid drift (brass, aluminium, hard wood) against the axle and nut, and with two or three solid hits with a large hammer the wheel hub should break free from the taper on the axle. Jack the machine up to remove wheel. When replacing wheel hub, grease the axle before installing, keeping grease clear of axle taper. Tighten axle nut firmly and re check for tightness after 5 to 10 hours of operation.
Note: If possible, pump up a flat tyre before trying to remove a rear wheel.
The wheels were designed to allow the tyres to be removed without removing the wheel. Jack machine up and break the tyre bead away from both sides of the rim, squeeze the tyre sides together and push down into well of rim and peel out over the bottom edge."
This at least confirms that there is no witchcraft involved, you have to pull the hub off that taper it is probably rusted onto. The kind of rough treatment with a hammer Cox recommends risks destroying the axle bearings if the hub is well rusted on - but note that if you do it the Cox way, the whole weight of the wheel and tyre, plus the tyre's adhesion to the concrete driveway, acts across the joint you are trying to separate when you hit the end of the axle with the biggest hammer you've got. If that inertia-based process doesn't work your parts are probably pretty well rusted on. If you have some experience with using a gas torch safely and controlling the temperatures various parts reach, some judicious heating of the hub but not the axle, in conjunction with a gear puller, is likely to help a lot. Sometimes people heat and cool the part a number of times, to enable the thermal expansion of the hub only, to gradually break the rust bonds. Personally, I'd work at getting the penetrant into the joint after the heating and cooling cycles.
