The following answers are personal opinion from our experiences. Others may have differing opinions and advice.
Tinsu's Battery Questions:
(1) Just want to verify that to remove the battery, should I disconnect the black cable first, then the red?
Black first. Actually, with the battery in the plastic battery box, it shouldn't be a problem. Most of the problems, when removing batteries or jumping vehicles, come from automotive engine, metal frame etc in close vicinity of the wrench.
(2) Wrap them in electrical tape?
Sure, that would keep them from touching each other or the battery posts.
(3) Remove the battery and store on top of a 2x4 in the garage.
Yes, if you are doing that because you are worried about theft. If theft is not an issue, as long as the cables are disconnected, the battery will be fine stored inside the black case on the camper
for several months.
(4) What should I do with the wrapped cables? Leave them in the black storage box and tighten it for the winter?
Sure, that would keep them out of the weather.
(5) I plan to do some winter camping at campgrounds with electrical? Do I need to reinstall the battery?
When you plug into AC, the "hot" cable will become "live" from the converter trying to charge the battery. With the battery unhooked (not present), the converter will also continue to run, believing the battery needs charged.
As a side note, you will not have DC power to run the refrigerator while traveling. You would
still have the propane operation option.
I will not use anything without electrical power. Would it be smart to include in case power went out to the gas furnace worked?
For sure, that would be a consideration. Having the battery with you would give you some insurance in that regard.
(6) My battery cables are connected with 1/4 inch nuts. I replaced them with wingnuts. Is there anything better for quick release?
No recommendations for optional quick release. A little advice about the wing nuts: take care to use stainless steel
wing nuts, so they won't corrode.