I have the Eldo calipers got the new $ones$ from the company that sells the new ones, I could find it if needed.
There is a reason GM only used that style parking brake for a few years on a big heavy vehicle, it is not a great design. Mine will hold my jeep in a gentle driveway but that is about it. I have it setup perfectly. Mine is a parking brake, if my breaks go out I will be down shifting or hitting something to stop. (but it does currently work better than the parking brake in my f250 which also passes inspection sooooo)
The hydro parking brake has come up on RME before, I think we decided that there is a difference between DOT and will pass utah saftey.
I seem to remember someone making some disk brake brackets for the 14 bolt (and others) that had provisions for the GM front style caliper and a smaller caliper for the parking brake.
In the Utah vehicle inspection manual all it seems to say (page 40)
http://publicsafety.utah.gov/highwaypatrol/safetyinspections/docs/2011-2012 SI PLT Manual.pdf
"M. PARKING BRAKE
1. Check holding ability.
a. REJECT when:
1) Parking brake does not operate or fails to hold vehicle.
2. Check ratchet or the locking device.
a. REJECT when:
1) Ratchet, pawl or other"
So nothing about having to be mechanical, it just has to hold the vehicle. A simple hydraulic system should pass inspection, but I don't think anyone has done it.
Also if you find a little hyro master cylinder that you can rig up to the factory e-brake lever be sure to take pics of that, because I want one too!
Here is a link to look at too
http://coloradok5.com/forums/showthread.php?p=2989860
Nathan
http://www.rme4x4.com/showthread.php?83436-Nathan-and-Tanja-s-99-XJ-Build-up