[urq] rear brake upgrade options

[Mike Fitton]

I'm thinking about upgrading my rear brakes.  Not that I feel they're 
not working hard enough, but I think the parking brake mechanism is 
seized.  If I have to take that much apart and do that much 
repair/replacement, I think it would be a great time to update some 
stuff back there.  I seem to recall hearing that the 20v 200 calipers 
with V8 rotors was a bolt-on...or something like that.  Can anyone 
elaborate?  I'll worry about the brake bias later.

-Cheers!
Mike