I have been playing around with a similar idea: Ability to change the Objective Lens - #5 by ffesti
I did not get beyond a few lines of OpenSCAD. Lessons learned so far:
Designing to print is not that easy. The OFM makes it look easy but they have put a lot of thought into that. This is pretty obvious if you start looking at the details but can be easily overlooked otherwise.
E.g. the optics modules are made to be printed objective up. So just dropping it onto the revolver will not print at all or require support and still not print great.
There is very little space between the objective thread and the tube lens. Getting the gab between the upper and lower piece of the revolver in between is not impossible but tricky - especially if you want to avoid support.
Printing bearing races without support works if you just cut out a 45° triangular ring. The result look pretty good. I still have changed my model to use two metal ball bearings on the axis as it feels less experimental for now.
While I have very limited experience with 3D printing I would never ever use a 3D printed linear rails for this. May be with metal rails (extruded aluminium or better) and a threaded rod/ metal screw. As this whole thing is going to be much bigger anyway, I would probably just use a (bigger) flexure with a bigger range of motion. Or allow the revolver to be mounted at different heights.
But as I have not build anything working yet take all of these with a generous amount of salt.