Well if you put your GN away already I will just cruise around here by myself! I am not ready to shut the door on this year, not with a weekend like we have just had and today being sunny as well.
As for storage, you can leave the battery in the car. Cold weather won't hurt it any. You don't have to disconnect it either unless you want to. I never do. Like to be able to know I can get the car out of the garage in a hurry if I have to. If the battery is in good condition it won’t even need a charge in the spring.
Don't need plastic on the garage floor in the winter. Condensation is not a concern unless you have a large source of warm moist air entering the garage.
You can use Stabil if you want. I have never used it and never had a problem starting any engine be it car..mower..blower...saw...etc. If you plan to leave the engine sit for a year or longer before starting it maybe. For 5 months I wouldn’t bother.
As for topping off the gas tank, I don't do that either. Am I a bad TR owner? I have never opened a gas tank to measure rust before and after storage so I don't know that any rust is more likely to form then than when you drive the car often and expose it to much more exchange of air i.e. filling and draining the tank repeatedly.
What I do is drain the gas currently in the tank come spring as the gas may have degraded and be of lower octane than today. Put it in a lesser vehicle like a Vette or Mustang.
Now...as for the one thing we can all agree upon....what to do about the mice. I live in the middle of the woods with mice waving at me from every corner of the property...and here is what WORKS if you can’t trap the little buggers with a dozen snap traps.
Irish Spring. Yup….the soap.
Cut the soap up into strips and place in the engine compartment. Try to keep it off things that you don't want to clean later as it leaves a soapy residue behind sometimes.
Put soap under the car around each tire as that is how they are getting up into the car. Just for giggles if you ever want to be horrified...put glue paper all around each tire for a month and see just how many you collect.
I have used Irish Spring for the last two years and have not had any problems. This is the first time my hood liner may not have to be replaced every few years. I don’t find mouse turds at all in the garage now either. I put some behind the headlights, down on the fender wells, up where the air intake for the vents is…etc…just not on anything metal.
And as an added bonus...your garage will smell 'springtime' fresh. It can be a bit overwhelming for the first week but I like the smell. You have to repeat the process annually as the soap disintegrates but no big deal. I keep it in the car in the summers too.