I want to convert to rear disc brakes, but need an e-brake. Is there any that work well and don't need constant adjustments? I've read a lot that rear discs stop a moving vehicle well, but don't necessarily hold that great as an e-brake. The small caddy calipers (79 and up) seem to cause a lot of grief, but some say they work fine. I think a lot of the complaints are due to poor adjustments, but there still is no consensus on whether they work well as an e-brake. I also read about using 89 T-bird or newer Explorer brakes, but can't find much detail on how well they work.

So, what can I bolt on to my rear D44 that will give me great stopping and holding power?

MK VIII or Crown Vic Police special 1996 and up, works good for me - self adjusting. But then I used the whole diff and later I can 4 link if if I get a wild hair.

my explorer rear brakes hold just fine, any brakes will hold you just have to adjust them

Before I found a complete explorer disc brake package for my 9 rear, I was looking at the late model +05 mustang rear calipers. They seem to be an updated version of the late 70's caddy calipers. Though they would require a custom mount, but its a two bolt set-up.

I have the small Caddy calipers. They're a pain to keep adjusted, but are adequate. The e-brake will hold on a steep incline, but always feels "tentative".
If I ever re-do the discs on the rear (an XJ D44), I'd do something else. Problem I've run into is rotor bolt patterns. Seems none of the available calipers with shoe-type e-brakes come in the 5 on 5.5 bolt pattern, which is my front pattern. This means you would have to re- drill the donor's rotors, something I'd rather not have to do.
The grand Cherokee rear discs will fit an XJ D44 rear with little moding, if the axle bolt pattern is acceptable to you.
The new Jeep JK's have a rear D44 and discs--another possibility.