I am currently replacing the rear brakes and bearing. I was able to get the bearing and collar low enough to get the c-clip on, but after doing so I realized that the wheel cylinder contacts the stud face preventing rotation and causing the backing plate to be uneven. I purchased the wheel cylinder from RockAuto and was hoping someone could tell me if the size of the wheel cylinder is wrong or if I did something incorrectly. The cylinder is mainly contacting the stud but is also only a few mm from contacting the back of the hub. I have made sure the stud is fully seated.

 

It ought to be a simple matter to compare the wheel cylinder you removed to the new one.

I might have done that before I installed the new one.