If you bin off the surround you should be able to re use the plate. Put an inch long strip of masking tape roughly down the middle of the plate vertically, measure and draw a line accurately marking the middle of the plate. Do the same with a horizontal line drawn in the middle of the plate on a horizontal strip of masking tape. Measure the fixing holes on the boot/tailgate probably plastic inserts then half it and measure from the centre out on the horizontal line. As above place on a block of wood and drill a 2mm diameter hole to start with. Gradually open up the holes a bit at a time until it's 1mm larger diameter than the fixings. That should do it.