I installed only front sensors in the license plate - CANADA 2005 Z4 3.0. I did not use the license plate cover unit. I cut holes in the plate, therefore no need to paint to colour match. Also, there are few places to install them. Height is 34 cm. I can describe and provide photos if anyone is interested. Got the unit from eBay.com which has a sensitivity adjustment. Installed the module in the dash behind the glove box, and power is from an available switched fuse using an adaptor. No display, just the beeper. Straightforward, easy- did not need to remove the bumper, but long. The Z4 is so short in the back, one could reach back and use fingers to touch the curb. lol