REAR Parking Sensors !

[palkid7]

Hi guys !
I was thinking about installing rear parking sensors, well , I am not that much expert in this thing ! a friend of mine told me that when I go to fix them I should ask them to keep them as low as possible !! well, dunno about that but does anyone of you have those ?! and can you please provide me pictures or rear bumper with the sensors !! and what type is prefered ! thanks !!
btw I drive a sedan !

[icspots]

Sealy at the Mz3 forum put some on his 5-door. I think he later decided he'd rather have them on the painted part of the bumper for better usefulness as where he has them they pick up the ground a bit too much.

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