I took the rough as guts approach of just tying the panel down with fencing wire, buffered by a bit of foam packing, though I did get fancy and put the cable into some conduit so the sun won't damage it.
The boards under the battery are genuine USA as I recycled them from the mower case. I blew money on a new battery and swapped it over on Cubby.
I suppose tomorrow I'll buy a new extension lead and cut the plug/socket off it.
I actually rather like spider webs (or at least the spiders who put so much effort into making them) so there's no danger of me using that web destroyer in the background.