Neither.
We rolled it back about 6 inches. This put all four wheels on the ground. Then we tied it to a stout tree and chocked the rear wheels. Was already in low diff lock so we put it in first and it held.
By luck the rock under the axle was both solid and perfectly horizontal. So we jacked up a couple of inches to remove the loading on the tyre.
Out came the compressor - a good one from a halfords type shop, nothing special. We hooked it up and turned it on.
Next we pulled the tyre so the bead was touching the rim and waited. A quick spray of WD40 and a few minutes later there was a loud bang and it was all done. It took about 30 PSI to seat and we left it like that for the rest of the day.
The tyre was at 22psi before hand. It had been on for 8 months, so should have stuck better than it did.
Behind the reaer wheels was a 12 inch drop, so the spare was so high it would have been very hard to get off!
Steve