Minor update.
I let the 3 bolts go which hold the clutch bracket in and this gives a bit more "wriggle room" to refit the clutch pedal.
There is now enough clearance between the pivot and the driveshaft tunnel to allow the pedal with bushes installed to slide on.
However, due to the tight fit of the bushes I suspect I am going to have to completely remove the bracket and put it in a vice to drive the bushes on.
To do this however, the brake pedal assembly complete with the extended bar which runs from the left side of the car to the right (as the servo is on the left and we here in UK drive on right!) will have to come out.
This is turning into quite a job for an amateur!