Sorry Doug but that's not the case although I appreciate your persistence as it's given me the opportunity to look deeper when I took the mount apart last night to prove and hopefully re-engineer. The reaction from dampers onto top mount is still exclusively via the rubber bushes the nut simply clamping upper washer and metal bush to spindle. They are unconstrained therefore within their elasticity to forces in the vertical plane and with help from grease I will use to movement against the 12mm o/d metal bush. Their position laterally is held to some degree by the inward facing lips of rubber bushes that match the considerably larger approx 17mm hole in top plate allowing elastic articulation when full lock approached. Leaving the metal bush loose it would be free to wear away the lower threads on shock spindle, movement of thick upper washer might also contribute, although wear here might be considered unimportant. Speaking of that large diameter washer it would unfortunately be in a very good position to unscrew nut with steering movement once it was loose as unlikely the opposite movement would retighten!
Brief measurements suggest the metal bush would be correct length to tighten against if it wasn't for the conical movement. I've ordered some stainless 12mm o/d x 1mm wall tubing and will experiment with bushes initially 1mm longer which should allow the rubbers to be turned. Note though there is a significant difference between wheels in straight ahead position when bushes are tolerably square to plate, and full lock which on close inspection shows considerable compression on one side of each bush. PB was unclear the position in which bush movement should be checked but I'm guessing straight ahead wheel position. Will get hold of some fresh top nuts as well, they are locking fine thread M10 and as best as I can measure 1mm pitch.
Let's face it the whole exercise is a bodge to correct a badly engineered design starting with the cantilever top mount plate that Peter Morgan introduced when he felt pressurised into introducing dampers in the first place. I was alarmed when I first set eyes on this arrangement and nothing has changed
