having a little difficulty removing the rear rotor, got the wheel off, removed the caliper, took out the hex screw, gave the rotor a slight tap, it moved, then it's being held on by some springs, (parking brake). i'm guessing i need to loosen the parking brake, but i can't find the "adjusting star" inside the rotor, it's a 94 c280. can i get some more specfics on where this star is. thank you.