OK, I'll take some photos of it tonight when I get home from work.
OK, here are some photos of my front plate bracket held on with magnets. To make this you need the OEM front plate bracket that came with your car from Lotus and you need to saw off the mounting studs (no holes to be drilled in the clam!). Now line the side that fits up to the plinth on the lower lip of the clam with some sticky backed neoprene foam ($1 from your local craft store) so it looks like this:
Now turn it over and attach your magnets (I used 5 rare earth neodymium magnets from eBay - $12 for 10) using 3M double side sticky mounting tape:
Next you need to get under the nose of the car and remove the aluminum filler panel that fits between the frame and the lower lip of the clam. Once you have this panel out you can access the back side of the plinth on the lower lip of the clam and attach the rest of the magnets you bought in the same pattern as the ones you mounted to the plate bracket. the easiest way to do this is to hold the bracket on the front of the plinth where you want it to be located and reach in behind the plinth with the magnet with sticky tape applied and let it position itself to the corresponding magnet on the bracket. These magnets naturally align themselves with each other so as long as you don't get too close to the wrong magnet it is pretty easy. Once you have them all attached in the right place, replace the filler panel and you are done. You can then pull off or replace the bracket as needed as shown in these photos:
The only problems I have had with this arrangement is when tossing the license plate/bracket in the trunk of the car, anything made of ferrous metal back there will attach itself to the bracket. I suppose the same applies to the nose of the car, but I haven't has any trouble with that. The only other thing is that this won't work on an Exige.