Seems like a good "outside the envelope" idea, which is always encouraged here. I am just trying to visualise the stress points, and angles of stress, if you know what I mean. Howabout a wider one, to fit "CBeam", with scope for a screw rod and nut? Try to follow it through. Just a thought? Gray
This looks very similar to the carriage that is sold here https://www.inventables.com/technologies/x-carriage-extrusion