As Murdo said the sticky pads for reg plates from Halfords will work just fine, just for peice of mind put 2 at each end and 2/3 in the middle and it will not fall off, i've stuck both mine on with 1 at each end and one in the middle, took some getting off when i replaced the plates for new ones with the forum address at the bottom of the plate, trust me it will not come off, we do over 50 cars a day so that over 100 plates
Cheers Phil