CrisPDuk

Giving my neighbour a lift with some work on his T plate 1.9 Z3 today and we've come across a conundrum

The rear hubs cosist of an outer disc for normal braking and an inner drum for the handbrake, similar to the Subaru set-up.
Unlike the Subaru however, the flimsy bit of tin that shields the disc is also the mounting plate for the handbrake mechanism. This flimsy bit of tin has now corroded away causing the handbrake to become a colection of parts within the drum, and for the life of us we cannot figure out how to get the plate of to replace it without destroying the rear wheel bearings.
We've tried asking the local BMW stealership for any tips but all they want us to do is bring it in for them to look at (and charge accordingly).

Anybody one here know how it's done?