Came out of the store today and found that Harlem’s right rear tire was flatter than the proverbial pancake. Tried using my inflator, to no avail. Went back inside and got a can of Fix-a-Flat, and still no good. Looks like I would have to do an old-fashioned tire change in the field. 
I got the spare wheel and the changing kit out of the boot w/o a problem (thanks in big part to some weight lifting I took up during the past 2-3 months). Problem did come though when I went to loosen the lug nuts. The user’s manual mentions that there should be an “extension” to the lug handle to make removal of the nuts easier (although it is NOT to be used when tightening the lugs back). However, although I had two full kits in the car (one was a leftover from an earlier Jag), I could find no such extension bar, which would presumably lock onto the other end of the lug handle (I could see a hole in the end with “teeth” around the inside diameter). There was no empty slot in either kit carrier, either, for any such extension handle. 
W/o that extra length for leverage, the nuts would NOT budge (probably put on with an impact wrench by the PO). 
I finally gave up, in the 94-degree heat, and called a bud who quickly came over with his handy hydraulic floor jack and 4-way wrench and did the change out in less than 15 minutes. 
(btw, the cause of the leak was apparently “dry rot” of the tire - the scourge of all tires in North Texas, esp. in the hot summer!)
