After a lot of research, the joint with the largest angle of movement that I can find in the uk is:
GM/Vauxhall BA0804 / QR3167S
Which allows 37 degrees free movement in either direction.
The thread on the taper is M12 x 1.5 pitch and on the shank is Female M14 x 1.5mm pitch. Both Right Hand.
Since nobody seemed to be able to answer this question - I thought it would be a good thing to put on file!
Si
