All sorted now - got the cover off with a small piece of wood with nails through to line up with the holes and a pair of needle nosed pliers. Its a left hand thead - clockwise to undo. a few scratches on the cover where its slipped but thats not seen anyway. I took 2 O rings out - one under the aforementioned cover which didnt affect the stiffness of the focus but i had trouble tightening the cover back up when putting it back together - it seemed to lock the focus wheel if too tight (yet nowhere near as tight as originaly). The O ring nearest the tube causes the stiffness as that one touches the focus knob housing as it turns. There is now a small amount of play in the wheel which is to be expected I guess as the O rings keep everything touching and tight. I have a MK1 Nikko with the same play - perhaps that has had O rings removed in past?
Anyway its much nicer to use now and as long as you range find in the same direction everytime the play wont be an issue.
Thanks to all