Pat, below is an image of my Tak FSQ-106. The OAG has since been removed (want one?
), but the image train is 4" focuser to M72 to 2" compression ring (Tak makes them SO fine there is NO slop - you fight air pressure installing things!). CCD has a 2" nosepiece with an M48 UV/IR up front, and screwed onto my IDAS copy T2 filter, which then screws onto the CCD.
No flex apparent, but I am waiting on my Precise Parts threaded adapter to arrive to mitigate it all.