I had to let out alot of air, and wiggle the spare tire down to allow the floor
to close unimpeded. Once the tire was in, I put in a little air back in,
but not much.
The main reason I did this was I did not like the runflat tire.
If you like your runflats, then you might not want to do this, maybe,
unless you are driving thru the Desert LOL
https://www.youtube.com/watch?v=c4zfI-WyOfQ