Now for the dumb question. I can't get the rotor off. Usually I pulled them off. This one has two small screws on the side but I don't know if thats whats holding them on or if I unscrew them some part underneath is going to fall off and I won't see how it came apart to get it back together again. Should I putting some more muscle into pulling it off or is the screws after all? This is a Mallory distributor.