Hi, one of these clips fell out of the rear calliper. I can't work out where this one goes. The other one sits under the piston, as you can see. Anyone? Oh, that clip that is in it is on the wrong side, I think. I just noticed.
It's the guide for the pads, at opposite end to the guide pin.
And yes that anti rattle spring that's in your caliper in the pic is the wrong way round, the triangle arrow should point in direct of rotation of the rotor through the caliper.