I looked at the homepage about the OEM hitch installation. I was agog!
then I googled hitches and found etrailer.com and an X5 6-bolt hitch that was rated 600/6000 Class III. I paid $124 US and got it delivered in 7 business days. At first I was surprised at how simple it looked. 4-left holes and 2-right after reading the instructions, I lifted the rear using jack and placed stands on the axles. I used a hex pin and a pneumatic ratchet to remove the 6 bolts. I placed the hitch and aligned the holes from below the frame, replaced the 6 bolts with the ones supplied from etrailer. I then creeped under the crossmember and drilled a hole according to the instructions, un bolted the hitch, placed the compression threaded grommet into hole. I put the bolt into the threads and torqued to specs, and replaced re-torqued to etrailers' specs the six bolts above. I dropped the jack and stands. the receiver sticks out of the oval plastic hole when I haul, but I unbolt the 7 screws and pop the plate back on. I spray the holes with WD-40 replace all the bolts and drive off sans hitch. I never had to drop the bumper or disconnect the sensors. The only electrical I had to do was to connect the lights through the designated port and plug into the trailer dongle.
I was done in 1 hour. My rides are a 1999 e46 328i and an 2005 X5 4.8is On e46fanatic.com you can visit my garage.
Looking back at the OEM install, I cringed.

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