FreeCAD and Rostock Max to the rescue
Not terribly complicated in the end but getting things to match up, to grip the hose without crushing the airway and to generally just all behave took a bit of work.
Very pleased with the result.
[img]http://www.simonlockwood.net/linky/3dp/hudclamp.jpg[/img]
And in place
[img]http://www.simonlockwood.net/linky/3dp/hudclamps.jpg[/img]