Sorry, bro. Sometimes it takes a while for the right person to read your post and provide and answer. But since you're in a hurry, I'll tell ya what I Know. Fleets just aren't my cup of tea, but......
Any HP washer will get the job done, so long as you choose the right nozzle. Probably no smaller than a 25 degree tip. Don't get too close to the finish, and keep the wand moving. The paint job will be fine. But as always, gpms---the more the better. Faster rinsing.
Definitely can't help ya with polishing tanks. But I can tell ya about cleaning them.
AlumaBrite Brand aluminum cleaner/brightener. Otherwise known as hydrofloric acid.
I wouldn't dilute it any weaker than to 10:1 with water, but no stronger than 3:1. Spray it on with a pump up sprayer, let it dwell just a few seconds. I'd say no more than 30 seconds. Depending on the strength. Leave it on too long, it will burn streaks into the finish, and is a PITA to get out. Rinse real good.
Be careful not to get the stuff on paint jobs or glass.
Remember, acid is only for cleaning and brightening, NOT for polishing.
PLEEEEEZZZZZ don't put the stuff on any polished surface, i.e., Chrome stacks, bumpers, etc. You will burn the hell out of the finish, and make a driver mad enough to spit right through you. I know. I used to be one!
Happy washing.
Randy