further to yestedays cry for help. the job is now done but using a slightly different method. The bolt head was on the brake pedal side & even removing the plunger from the brake pedal & carpet etc would not allow the arm to move far enough back to remove the bolt. Pulling the pedal forward after bending part of the dash/steering mounting out of the way almost did the trick but still left about 1mm to little clearance. The answer for me was this:
Remove the nut from the pivot bolt & push the bolt out a little. clamp the bolt to stop it turning, I used mole grips, then saw off the head of the bolt with a hacksaw blade. this only takes a minute.
You can then slde the bolt out. I reused the bolt by winding a nut on & buring the cut end over to stop it coming off but a new bolt 1/2 cm shorter than the original would be better. The whole lot went back together with the nut on the brake pedal side in about 20mins.
Doing it this way means you only need to take off the trim in the footwell nothing else need be touched. So the whole job should only take an hour. Makes you wonder why Citroen didn't fit a shorter bolt from the otherside in the first place.
Happy new year.