Changed the front bonnet badge on mine this afternoon. It turned out easier than i expected - i've heard some dealers recommend removing the front bumper to do it and quote for around 3 - 4 hours labour. It took me much less than that to do it as follows:
1) Mask around the badge using tape (just in case you slip)
2) Cut out a small square in the centre of the old badge using a dremel with a suitable attachment to expose the top of the nut inside. The badge will get very hot in this step and may require several passes, be sure not to let it get too hot as i noticed a small amount of the masking tape glue has marked the paintwork, possibly due to the heat in this step? Having tried meths, claying, polishing etc and still failing to remove these small marks i would say if you are confident with the dremel it may be better not to mask it off at all. I am pretty fussy over my paintwork though...
3) Grind the top of the nut off at which point it will fall on to a shelf above the front grill,
4) Gently prise the old badge off its sticky backed plastic fitting and discard,
5) Peel off the old glue residue and clean the surface thoroughly so the new badge sticks firmly,
6) Stick the new badge on!
If you want to retrieve the old nut and washer remove the front grill and there is plenty of space to reach up on to the shelf in front of the radiator and retrieve them.
