rear brake shim needed vfr700 ?

I have a 87 vfr700. Looking at the service manual I see the 86 vfr had some kind of shim between the rear brake pad and caliper body. The 87 doesn't have that pad shim. Do this part do anything useful ?

The reason I ask is I changed the rear pads (cleaned the pistons, sanded the pad slider pins, flushed the fluid, etc) now the inside pad is loose. With brake pedal engaged the inside pad isn't making strong contact with the rotor but the outside pad (against the pistons) does. I am wondering if that pad shim is meant to solve this problem. I think I went overboard with the slider pins. I took a round file to the new pad get it to slide on the pins, now the pad is way loose.

Some calipers I've seen use spring clips to keep the pads against the rotor when the brake is disengaged. I far as I can tell, this caliper uses rubber nubs for the same task.