I have just got a parking sensor kit. To fit it involves drilling 4 22mm holes in the rear bumber. Has anyone done this before?
What I need to know is the best place to drill the holes to make sure that there is about 25mm clearance behind the sensors.

I don't want to be doing this twice!

 

Your local dealer could do the install if you want to pass. The link has some nice pictures to give you an idea of where the sensors should be located if you want to have a go at it, good luck.
http://www.cardomain.com/ride/3204914

 

I installed a kit such as what you describe, in my old c70. There is plenty of room (clearance) to install the four units.............make sure the two outside ones are closer to the corners of the vehicle. I mounted the 'horn' under the drivers seat by velcro to the carpet.

r.