I have a fairly new Shimano rear derailleur on a cheap department store MTB a friend gave me. Recently the derailleur (particularly the jockey wheels) have started to rub against the chassis in high gears. I tried reseating it on the hanger at a larger angle, but even as far as it will go, it just wants to spring back until it hits the chassis. The best I can get it has it with very little clearance.
Here are some pictures:
Zoomed in so we can see the derailleur hanger (with "Hole A") that is bolted to the frame. It doesn't move when the axle is loosened.
I don't particularly care for the paint job, but I do want it to stop hitting against the chassis and risk affecting operation. How do I fix it?