No, I didn't is the short answer
The reason I was repacking it was that I had noticed some heat tarnish near the front of the can (and I thought it had got a little louder)
On opening it up I found the steel wool holed where the heat tarnish was and the insulation at that end quite blackened.
So I didn't want to put the steel wool back, so I spoke to Kirsty (I think) at TV and she said that I shouldn't need any retainer at all, just use the infill.
I repacked it with just the infill which are the pictures you can see, but before I had chance to run it up, I visited our exhaust factory in France who use a glass cloth as a retainer in our large industrial silencers.
I mananged to acquire a bit and reassembled the exhaust with the thin layer of glass cloth, feeling happier that there was some sort of retainer present.
On testing it, I am not sure it is is as quiet as I expected, so perhaps the glass cloth is preventing the infill doing its thing.
I will run it a bit longer and dismantle again to see how it is all faring
Rik