2 possibilities:-

1) Get yourself to Halfrauds and buy a pack of proper adhesive pads for number plates.

2) You can buy either rawlplugs or fancy caged nuts from places like B&Q.

The number plates on my BMW are held on with sticky pads with no problems.

The only worry is that if you have an import, and have to fit a double row plate, the plate is hanging down below the rear skirt so air passing underneath the car will always be pulling on the plate as you drive.

The caged nuts are brilliant.

It's a nut fitted into a sort of metal rawl-plug.

You drill a hole that is sized so that the nut can't push all the way through the panel.

As you tighten the screw

(without the number plate attached) into the nut the cage spreads out behind the panel to clamp the nut in place.

You then loosen the bolt

(or screw), fit the plate and tighten the screw into the now solidly clamped nut.

Simpler, of course, you can just drill out the holes then stuff a couple of rawlplugs in and fix the plate on with self-tappers screwed into the rawlplugs.

Personally, I try to always fit plates with sticky pads these days.

Whenever you fit them with screws you end up with water-stains on the plate near the screw holes.
