4 maintenance questions

[tkd]

I have 3 questions.

07 Nomad, 11K and I am slowly getting through the bike as I didn't buy it new and want to be sure everything is up to par on fluids. I have already done the oil.

1. Brake Fluid. My right brake fluid window is showing that the fluid is starting to turn. It's not as clear as the left, but that's expected from the amount of use I would assume. The fluid is still plenty clear to see the 3 slots, The color is just slightly darker than the rear. What's a good indicator for changing it.

2. Rear gear oil. It was changed at 7500. I plan on doing it at the next oil change

3. Coolant. All seems to be fine. Between the lines and still green. My guess is it's the orginal. I live in MN so I am facing 0 F in my garage unless I can get it into the basement, but I think the bars are too wide for the sliding door.

4. SwingArm. The one I am dreading. No record if it has been done and I don't have the time or equipment to do it myself.

Can anyone give some advice and maybe rank these in order of priority?

Thanks