I'm starting work on the filter wheel assembly...  I'm going with a semi-flat wheel with the filters mounted to its face.. It's a throwback to my first idea, and it turns out it's pretty common.. I only have two filters to mount in it for now, but it leaves room for expansion.  The circumference is geared and driven by a stepper motor..I might add index points or maybe a rotary encoder to track position.. we'll see..  Here's a preview, I still need to split it in half, add screw holes, a center shaft and bearing, and the filter mounts of course...

Here it is in its place just off the beam splitter next to the laser emitter...