I knew I hadn't been imagining it when I saw one or two!!
Looks like Google have finally got round to processing images from their Streetview bike then. About 3 years ago I went round Chester city walls, and noticed one or two WRTL 2000s cut in half - quite a peculiar solution!
http://goo.gl/maps/mL9ZN - the canopy has gone in this, but you can see the 'tabs' across the bowl where the wall and seal slots in place. I believe this is the one I actually saw from above on the city walls.
There's actually SIX of those wall mounted chop-off 2000s
http://goo.gl/maps/nKTKthttp://goo.gl/maps/Yl9Datwo in this view:
http://goo.gl/maps/zlQY9http://goo.gl/maps/mCzZ7Plus considering the height of the cliff and how narrow the towpath is, I cannot help but wonder how those were actually installed in any form of safe manner....