How to Fix Broken Headlight Mounts On BMW 850i
Ever since I got the car my headlights were always having some sort of problems. Over the last few years I sorted most of them out (electronics, wiring etc), but this one I kept putting off.
Whenever I would drive on a rough patch of road my lights would look like they are having a seizure. Thebiggest problem with this wasn't even the fact that it was annoying (beyond annoying), but the fact that it blinded EVERYONE on the road (especially with the HID's). Here is how I fixed my headlight mounting points.
After a quick inspection I found that the mounting points on the linkage to the motor was completely snapped, and only the inner side was being held up.
First pull out your headlight buckets entirely. Take off the top aluminum cover, then unbolt the four 17mm bolts that hold the bucket to the car. There are also two metal structural components that the backs of the headlights mount to (these need to come out so the connectors can come out). See picture below:

Here are what my mounts looked like when I pulled the headlight buckets out. Completely broken off, and by the look of it one of the previous owners tried gluing this together...

The next step is to further disassemble the headlights by taking off the 13mm nut on the mount. The inside can be grabbed using a 15mm wrench (just a really tight fit).

After removing the broken tab you have to grind down all of the remaining mount that is left on the bucket. I did this using a dremel.

The buckets are now ready. The next thing I did was - creating the new mounts. I used some strong aircraft grade aluminum. Not very thick - just so it is easier to work with. I mocked it up with a pencil on the L shaped piece of aluminum first. To determine where to drill the holes I put the buckets up manually and double checked by placing it approximately where the old mount was. (There is some room to play with here - doesn't need to be SUPER exact - the closer to the original spec the better). I drilled the holes after I marked the holes with a pencil. One thing to note, the two of my pods were a bit different and the tabs had to be a bit different - not 100% sure if its like this on your car.

Then I used some plexiglass to compensate for the gap for mounting. I clamped the two together and drilled holes this way.

After I drilled the mounts I used them and propped them up into their positions on the buckets, and using the trusty pencil marked the spots on the pod that needed to be drilled for the mounting.

I used some regular bolts, washers and nuts to put the whole ordeal together.

Almost done! This is what my mount looks like after being bolted up. A good idea is to put some black silicone into the bolt holes and a bit around. After this all you have to put on the 13mm nut, tighten and coat it in some black paint!

After you assemble everything make sure everything is aligned and on the same height. Bye-bye seizure lights!

