On Thu, 22 Nov 2007 21:34:48 -0500, "Scotty" wrote:

Do you have room to install a collar, with a small disc for
a cable actuated caliper of some sort. Like a bicycle
brake, only larger.

The collar would probably be easy although there is nothing available
off the shelf that I'm aware of. The difficult part would be creating
a secure attachment point for the caliper. Given the forces involved,
the caliper itself would need to be hydraulically actuated like a disc
brake.