There's a picture of it attached to bars on these amazon reviews. Looks like a good option. The green silent runner has a 4" deep track - which is really quite big and bulky.
Wish I'd seen the savic orbital as an option for a cage mounted wheel! I didn't know much about them. Is it noisy?
https://www.amazon.co.uk/Savic-27-La.../dp/B005FLSRJA