From what I understand from others, you gotta get it out of there or it will rot the carpet.

I had mine out last year. I had the luxury of two things, Texas summer and time. I left mine out for weeks. I worked on the car, the dash, the accessory wiring all while it dried out with 100+ degree high temps. When I remember checking it, it took probably about three days before it would have been possible to reinstall without mildew, but my bet is that would have been too soon.

If I had to do this at this time of year and still drive the car every day, I think I'd remove the carpet to clean and then put the seats and everything back in and just go without it while I had it out to clean and dry. If you have carpet type floor mats it might be liveable for a time. I have a garage but it isn't heated. A big garage with heat and space enough to let this be hung up to drip would be the best you could hope for.

When I had my dash pulled out, I pulled seats console, rear deck trim and carpet to install some wiring and put down some dynamat. The carpet was out so why not try and clean it up. I used a canned carpet cleaner and worked it through the carpet with a heard plastic wide putty knife and any other similar instruments I could find. I tried a rolling pin but that was never gonna work. The way the backing is vacuum formed to the carpet, it can hold quite a bit of water. I 'pushed' as much water as I could to the edges and toweled it up. I'd squeeze the towel dry and go again. When I couldn't bring any more water out, I put it out in the sun for a couple of hours and then hung it up in the garage to drip. Once it had been hung up over night it was very wet at the bottom edge. I could then push quite a bit more water out of it, taking care to keep it tilted at an angle so the water wouldn't just flow back into it.

Good luck, I hate that you to have to do this in winter.