Okey Cokey!!!! -latest update and pleased to report success!!!
What did I learn?
1. It's a bit of a ball ache
2. I removed (as per advice received via the thread posted) the rear hugger, side panels and rear light assembly. All easy to do.
3. I also removed the cans and two pipes from the Y piece.
4. I opened up both the ends of the two pipes where the bolts for tightening are and the ends of the cans to give more movement.
5. Copious amounts of copaslip on pipes and silencers and red rubber grease on the rubber mounting cushions on the cans and the two mounting pins was applied.
6. Visibility to see if the cans are located on the pins is "difficult" shall we say. A small torch is a good idea.
7. I had to lift the cans higher than I thought I ended to to get everything to line up. The flared nature of the entry into the cans doesn't help.
8. Once everything is lubed and lined up (trial and error was needed here) the pipes went on helped by gentle use of a rubber mallet. Wiggling the pipes up and down plus side to side helps. Copious use of F*+k, S*+t and b*^^+*^s didn't help strangely!
9. Once fitted, the two brackets for the springs holding the cans to the pipes are approximately 87-88mm apart centre to centre.
10. The tightening bolt for the curved exhaust pipe is close to the bottom bolt head for the rear shock while its tightened up but is clear once tightened.
11. Locate the cans on the two pipes slightly so the cans can engage with the two mounting pins. Lift the cans up higher than you might imagine is necessary and wiggle, twist and push forwards. It's a god idea to leave the bike in gear or with the front wheel against a wall in case you push too hard. I was always worried the bike might move off of its side stand.
Thanks to members who offered advice! It's worth the effort - system looks great and sounds luverly!