It was actually the inboard PAD on the o/s caliper that was jammed, enough rust had built up on the edge to jam it, new discs and pads went on today, only greenstuff, only cost £20(new, long story!!), going back for re-mot thursday.
These brakes are just temporary though as have my nice new 17's and tarox 6 pots/330mm to go on.
tabetha