Unbelieveable. How the f**k is bilberry good on thorough grime? I dont get why people reccomend it as a powerful wheelcleaner. I use it diluted on protected wheels, undiluted it still isnt very strong.
Annoyingly itll probably take more than one product.
Non acidic powerful wheel cleaner would be Espuma Revolution, great at cutting through yellow baked on dust and other shite. There are 1Ltr bottles available if you look for them rarther than 5ltr. Use undiluted. My favorite product.
Acidic would be Megs Wheel brightner, Or car plan Wonder wheels. If you use these be sure to give the alloys a thorough rinsing with shampoo. Undiluted again. Acidic isnt necesseserily stronger. Megs is available at i4d or Cleanyourcar i think, and Carplan is available at Halfrauds, or in supermarkets.
Tar removal would be tardis, try find a sample perhaps?
If you have pitting (google it - black spots) youll need a fallout remover, Autosmart fallout remover isnt hugely expensive youll find it on ebay if you look, usually takes a few hits and lots of aggitation.
Whichever one you do, get a small detailing brush so you can aggitate the product once applied. Id also take the time to protect them once youve done them, get some Collinite 476s or FK1000p, should last a few months if you wash carefully using something like diluted bilberry. Youll also have some sealant for your paintwork if you want to apply it so kill 2 birds with one stone so to speak. I dont know if you already have this.