Brake line...do you mean pneumatic line for tire inflation system?
http://www.pointedthree.com/disc/forums/showthread.php?tid=16758&start=1
Ignoring the fiddly bits like that.
These designs are seriously flawed for G4 COIN operations. They should not be considered for use outside of very secure areas, unless there is a hidden "boat hull" curve on the bottom of the passenger compartment.