Help with years of junk

[SATracker]

A guy brought in a Mini Cooper for a wash and wax. The process was CG Glossworkz, Pinnacle clay w/ONR as the lubricant, buffed with Optimum GPS; it turned out nice but I had a couple of issues that were beyond a car wash and wax- and I showed the owner.
1) on the painted white wheels was years of baked in brake dust. 1) wash was with CG Diablo, 2) went back later with Sonax Wheel Cleaner, 3) went back later with steamer. There's still backed on brake dust, if not pitted. The wheels looked much better than when the car came in but he agreed to let me practice on them. For years of severely baked brake dust- any thoughts? I don't want to damage the wheels and some of the brake dust is really baked on, parts of the wheels seem to be pitted.
2) the Mini has a turbo with dual exhaust in the center of the car. Over the years, exhaust has almost damaged the paint. Washing had no affect, steaming had no affect. I after I washed and clayed the first time, I clayed again w/ Meguiar's aggressive clay- no noticeable affect. The owner knows it's been years accumulating; it's almost like its baked onto the paint. I pointed it out to the owner and had him feel the difference between the exhaust affected areas and not affected areas. He was pleased with the way the car turned out but agreed to let me experiment. How do you remove years and of baked on exhaust from paint?
Traces of the exhaust fumes can be seen in first pic, right above emblem- brownish in color.

[Buster906]

You could try M105 and a magic eraser on the wheels. Try magic eraser and Megs Solo Cut on the exhaust

[rlmccarty2000]

For the brake dust you could try Iror-X paste, if you can find it.