Thanks to Randy Webb (http://www.cigarboxnation.com/forum/topics/adjustable-bridge-w-perfect)
I copied and modified his design a bit. Rather than carve the whole piece from expensive bone, I used scrap walnut from the fretboard and just a chip of bone nut. There is plenty of friction between the wood and box that it doesn't need the side retainers. I'm using an internal tailpiece carved from 1/8" brass stock screwed to a bolt-on, semi-through neck. Good break angle and less clutter hiding the box. I love the box art and try to show as much as I can. It sounds great, but I already delivered it so no sound clips...
I built for ball-end strings so opening the mando string set and finding loop ends threw me for a bit. A short length of 1/8" brass rod was simple solution. Adjusting intonation was breeze with the eraser end of a pencil.
Thanks Randy and CBN for all the advice,
Huntz
Replies

The wedges will make for a fine adjustment, but may be finicky. I reckon it would take more time to make the wedges than to sneak up on the setting by careful filing, a touch of epoxy if you go too far.
If you just want to swich between finger pickin' and slide, two different height slots would work.
Even better, two different height notches in the bone.Iggy said:

I reckon height adjust as two shims ought to work. I'll sketch it up when I get to work, and give it a whirl later this week. Huntz