My dealer threw in a spare, T125/80R16 on a fusion rim as part of the deal. It fits the trunk. Due to the blizzard/cold here, I have not tried it on the car. (14 Hy Ti with 18 inch wheels) I may do some shopping for jacks on line today. I have a 24 inch breaker bar with a 3/4 deep socket wrench that fits in the wheel well. Once I get a Jack I may look into attaching it and the breaker bar to under the rear window shelf.
I'll report back once I test it out. With the weather forecasts I hear today, it may be a while.