So in the meantime, we approach the issue from the left and remove that sides cap-screw/bolts/cover for the swingarm pivot – but this time I consult my mates at Google first, me being a fast learner, and see this side is indeed threaded, and extends into the engine casing, thereby centering the swingarm on the bike. Cunning. Pity this side has a collared bush that is ALSO corroded on and stuck solid. And it cant slide out, being collared…..
This is what its supposed to look like, both sides….

And here is the offending collar – the screwdriver is against a section that I snapped off trying to hold it with a pair of water-pump pliers – the bush is supposed to turn on the threaded shaft and stay in the swingarm when the bolt is extracted through it.

But no, its solid. And as I have damaged it already, I know I must replace it, so off to the Extreme Violence Corner for a crowbar. Obvious choice for breaking shit. No question. In minutes the collar was broken off and the mini-grinder was employed to remove the last vestiges of a collared bush…. Application of a 10mm Allen key removed the bolt, complete with seized bush through the remnants of the swingarm bearing cage….. Did I mention the bearings? They came out in pieces, what was left of them anyway. Cant help thinking he ride musta been a bit rough…..

At this point I realised I could remove the right section of the frame by removing the 3 bolts holding onto the main frame/backbone and have easier access to the right stuck bolts whilst working on the bench. Cunning plan. Do it.