Nice pickguard! There are stronger double face tapes used for automotive trim available. Maybe a local body shop would let you have a couple pieces for this.
I have been working with a "guitar doctor", and he said there is a product that is double sided sticky, very thin and this would be the ticket. If I can worm a sample out of him would you like to try it?
Thanks Christine for the offer. I'm going to give Roberts suggestion a try, it should be easy enough to get. But if that doesn't work I'll let you know.
Mike, I got double sided duct tape at wallmart -used for carpet and the like-I put it on the back of practice plates on wood or plates-hammer push power impact-acetone or pry it off-give it a shot-Fred