Just out of curiosity, why do the bolsters have to be removable? Even on the exchange a blade setups and stuff they stay in place.
Your idea sounds like it would work, but like george said, you can't have the heades protrude on the inside. And the real problem with that, is that to recess them, the liners have to be alot thicker than normal for it to have any strength. And you can't grind them flush or have them contact the tang at all because it will ruin the heads and then make it impossible to take the screws out without drilling the heads off or somehting like that. I would leave the heads exposed on the outside if possible, and either hide the pivot pin in a blind hole, or use a screw type pivot.
Depending on how stong it has to be, and the type of material they butt up against, you could get by with just a screw tyope piviot pin. The trick would be to dovetail the bolsters and handle material so that they fit together really well. The handle material would hold the bolster square and the pivot screw would hold it down.
When I say dovetail I mean that you mill the bolster off at an angle like this \ so that it overlaps the handle material.
They would meet up like this
handle\bolster.
Good luck however you do it.
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It'll feel better when it stops hurting.
