Having failed to remove the hubs from the quill shafts with a standard hub - puller, in the end I took the quill shaft back to the engineers and they removed them in minutes using a press. Apparently the proces requires a 50 ton press, and when the hubs do finally separate, they go with a huge bang. This leaves you with the quill shafts with outer bearings still attached.
The outter bearing is hard up against a shoulder as you can see. Removing the bearing is not easy. In the end I knocked off the brearings leaving this:
Then, with a very sharp cold chisel, I tapped between the bearing and the shoulder to gradually move the race down the shaft. When it was far enough down the shaft, I carefully ground a cut almost through the race. Then I used a cold chisel to open the cut and knock the race off. Nail biting stuff, but it worked for me.
I would like to say that the new bearings go back on easily, and they do, sort of. My first (expensive) effort involved pushing the bearing as far as it would go manually then, opening the jaws of my vice far enough to let the shaft pass through but not the bearing, and tapping the shaft through the bearing. Works great, but when I picked up the shaft, all the bearings fell out. I had bent the bearing guide out of shape. Don't do this! You will then have to cut the bearing race off again!
Finally, to get the new bearing back on the shaft I pressed them over the splines as far as it would go easily, then used a tube that would just fit over the shaft as a drift and tapped the bearing into place. Easy.
Having got the new bearing on, getting the quill shaft back in and the bearings adjusted is a fiddle, but not difficult.
I first assembled the shaft and bearings without the oil seals or squash tube. Then I tightened up the drive flange on the shaft until the bearings were just loose enough to give free movement.At this point I checked that the hole for the split pin was clear of the castellated nut and I marked the nut and the shaft. Then I greased the bearings, fitted the squash tube the inner oil seal and tightened the drive flange nut till the marks aligned. This needed some pretty heavy hauling on the socket wrench to deform the squash tube, but it worked fine.
Eventually.
I could then fit the front oil seal.
.and the brake back plate:
The hub:
The brake adjuster and the brake slave cylender:
and trial fit the upright
