John brought next idea :
Can anyone recommend a good strong glue that isn't a liquid? I need to put it
on a vertical surface but obviously don't want to have it all dribble down. I
have no faith in Superglue - the only thing I've ever seen it stick is skin!

It's actually to mount my LPG control switch in position in the car. They're
self-adhesive but for some reason this just won't stay stuck on. You can see
what it's for he

http://i137.photobucket.com/albums/q...doo/switch.jpg

Just to put this one to bed, I went with Evostik Impact contact
adhesive and it did the job brilliantly, but thanks for all
contributions and suggestions ^^