rear disc brakes on 8 3/4

I'm glad GMachineDartGT and I are in agreement, I feel the same way about cheap vs good.

IIRC the exact application for the brakes is a 2003 Ford Mustang Cobra. I'm not sure if those were sold in Europe (probably not), but here in the states, the basic service parts are seriously easy to get and actually quite cheap. Chances are EBC can send them to you since they are out of the UK and bypass buying them in the USA and having them shipped.