Generally I use the parts cleaner for everything so accumulates in the workshop, where one does not get further with isopropanol. Especially good is the whole way, even just as a tip to remove old stickers or AU plaques residue.
I use nurnoch the Brake Cleaner Liquid Moly, previously I always cheap used is often offered as here at Amazon in sets of 10. In little things you do not realize it, but in really stubborn dirt you can clearly see the difference.
