Every cloud@mrscalex (and actually, *everyone else*) thanks as well for your input, and the thread related to cutting the axis side...
I'm /fairly/ sure I should be ok once the washer is cut, the two parts move a little bit, given enough persuasion. won't rotate, but they 'rock' a bit, so they are not entirely seized. Seriously that mirror assembly is both completely overbuilt AND fragile at the same time, hard to beat
Anyway, I'm glad I planned a bit longer than a few hours for that job ;-) Also had to repair the inside of the door card that has been 'pulled' bit too carelessly before, and superglue&clamp some of the leather trim.
Tony.