04 Miata Rear Brake Pads - HELP!

Need some advice on swapping out rears. Fronts were a piece of cake. Any freebies out there?
Also looking for a taller ratio rear-end gear set, for better hwy mileage.

Grampazoomzoom

there is a 14mm bolt directly behind the piston. make sure its not the one that holds down brake line. behind that there is a hex bolt, loosen that to retract the piston and tighten it back or else you will have no hand brake. as the the rear end there aren't really a whole lot of options, should get decent mpg even though it is kinda annoying how high it revs at highway speeds