Re:
I can't send pictures, as I left the bikes at my in-laws after the weekend, but I can tell you how it was done.
First was replacing the steering bolt. Whyte uses a cap head bolt with a very prominent head on it, I replaced this with a normal hex head bolt. To sneak a couple of extra mm of clearance I machined the head down a little and gave it a domed profile. I used a lathe, but you could easily do the same thing by spinning the bolt in a drill and shaping the head on a file.
Second was the big gripper bobbins. The front bobbins have a 9mm hole to accept the standard quick release wheel axles. I drilled these to 10mm (same as rear bobbins) and then used shim steel cut into 4 0.25mm thick semi-circular shims to close one side of the hole down by 1mm. This effectively offsets the axle centreline by 0.5mm from the centreline of the bobbins. Line the two bobbins up relative to one another to maintain alignment.
Lastly, I put 0.5mm shims into the big gripper cutouts on the fork legs.
Total result was to push the axle down and forward from the crown by 1.0mm, which is enough to run the 2.0" tyres without rubbing. There's next to no mud clearance space, but I don't ride in mud anyway, and wanted sonething that would roll super fast on the sort of gravel trails I normally use. If I need to get really dirty then the 26" wheel will drop straight back in.
The only issue I have left to resolve is the slight interference between the tyre and the lower shock bushing at full compression. With normal fox bushings there's no problem, but with the modified (and much bigger) Whyte ball bearing based bushing there's a slight rub when the shock bottoms out. I might just live with it, or I might revert to the fox bushing instead. More concerning to me though is why I'm bottoming out, which appears to be pie related.
All this aggro can of course be avoided by a) fitting a smaller tyre
Or b) sticking with a 26" front wheel.
I only did it to see if it could be done, there's no competitive edge being sought and I had no performance gains in mind, but having acquired the wheels it seemed like it was worth trying. Having tried and failed with 2.25" and 2.1" tyres these 2.0" tyres were going on whether they fitted or not, but next time I change I'll fit narrower rubber. A 1.9" would probably be perfect.
Was it worth it? Well, it rolls really nicely, It looks pretty unique, and it seems to fit my 6'3" frame rather better. Plus, I can go back to 26" in about 20 seconds, so yes, it was a fun little project and it'll probably stay as a 650b for the time being.