I made some good progress after work this evening. I cut out the hole in the MIP for the instrument monitor and replaced the MIP. I fixed the monitor in place using a couple of old shelf brackets I had lying around, which seems to work really well.
I also screwed the throttle quadrants in position.
So now it's starting to look more like a cockpit.
I'll take a picture.
I only had time for a quick test, but my mind is now turning to gauge add-ons, as the default FSX ones look pretty crap when undocked on the separate monitor.
I'll add a tutorial on how to undock and move panels, and save flights.