1. You will not only be concerned about how far from the pump; but how much space in front. I can usually put the rig about as far away as possible (and still rich the nozzle) and be able to make the turn.
2. Depends on the turn. the 5th will cut the corner more than your rear end. I swing wide, as wide as possible and and make all the allowances I can. It is still something I find takes lots of paying attention.
3. Don't know your hitch, I have a B&W slider and it makes some noise at start and stop simply from the nature of all the parts.
Do you hear it only at start and stop? Could be the hitch, or not. It is worth spending some time with the windows down and listening I would think.
4. That is not many hours if it is original with your Fuzion
5. I don't know how your mirrors are, mine are just shy of seeing down the side of the 5th. Our is 8.5 wide, I think an 8' I could see down the side. That being said, I don't have any problems as one is seldom perfectly straight all the time so you can get good views from one mirror or the other most of the time. I would not go the extra for the side mirrors. It depends on your comfort level or experience. I have driven so many wide trailers that I have learned to compensate and stay vigilant.
The newer rigs have them available for a price and if buying new I probably would not order them, just my opinion.
Ours is under the hay cover for the winter, looks like you may be able to use it this winter from your picture... have fun.
-brent