Use a drift pin or a small diameter punch to knock the pins toward the center of the car. The pins rely on friction to keep them in place. Once you remove them you'll quickly understand how they function. Realize you need to completely retract the caliper pistons so the new brake pads will slip into the caliper. If you are at all unsure about how to replace the rear brake pads and ensure the RR caliper is functioning properly consider asking an experienced person for assistance.

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Fred Hoelzle