i have recently bought a dufour 1800 and need to replace one of the stanchions. it looks like they are a simple twist and pull jobby, being held in place by a key on the stanchion which fits into a slot in the deck fitting. however, twist, turn and pull every which way and i cannot get the thing out of its socket. does anyone have any tips that may help. many thanks. tonyhansen@adny.co.uk