Originally Posted by eagletangogreen
Dont quote me on this but I am pretty sure that the same St-60 witch is the 6piston calipers from the Z is the same as on the M just the brackets are diffrent to mount them on the particular car.. So if this is true you could buy some and just order the bracket from stoptech to mount on your M.
The caliper will be the same but the piston sizes probably will not. It is the same ST-60 caliper but Stoptech has a lot of variations on piston size combinations depending on the application. If you can manage to find out which combination they are using and what other cars that applies to, then you can get the same rear kit and have a fully balanced kit. I'm not sure how much money you will save in the end though.