I got the Poly 26 unit on the bike. The only obvious fixing points were the ones in the picture below so I fitted it on with them so I could see where else it would attach.
The problem is there isn't anywhere else that comes anywhere near the subframe. I made up a bracket that sits where the rear seat lock goes and fixed a couple of additional bolts through. Actually feels pretty solid.
In the meantime I decided to relocate the battery under the seat hump. If you're a fan of mass centralisation, look away now.
I started off by making this cut to the original battery box
Then I fixed it to the rear of the subframe. I've also reused the battery support from the tank bracket which has been battered into submission to provide the fourth side of the box. Bodgetastic!
Ignore the rusty bolts and rough finish. It's just a mock up at the moment using what I found on the garage floor.
Just to finish off, I put the seat unit back on with the undertray fitted using DZUS fairing fasteners.