Yeah glad to help out again
Best material for that mounting solution is good old BLUE TACK yep, if you find you get a bit to much movement after mounting, 1/2 a tube of liquid nails should do it, but make sure you mask the area as the bleeding of liquid nails can be hard to remove on compleation.
The good thing with the BLUE TACK is, if it not suitable you can reuse it and mount some girly posters in the boot on the underside of the boot lid.
any time