Answering my own question now that I've done the swap. We were not able to easily fit all 4 21s in the car. The SC also didn't have a great way of padding them to keep the dirt/scratches off the interior. We just collapsed some boxes and laid them down. I was going to bring some furniture padding blankets from moving, but they said over the phone not to worry about it. Not complaining, just pointing this out in case anyone else reads this before swapping wheels. Anyway, we got two in the back with the seats down. They won't fit in the frunk at all. They don't quite fit in the rear floor area, even with the passenger seat all the way forward, at least without squeezing - they weren't comfortable doing that without more padding for the leather and the center console, and I appreciate the concern. I think we could have stuck one more in there, but no sense in putting in all that work if I'm going back to pick up another one anyway.
