I got the new tensioner installed and it works great. It turns out the tensioner is actually from 2014 and looks very new. Both pulley bearings were completely silent and might as well have been brand new. Unfortunately, it didn't fix the engine shake issue, but I didn't expect it to either. I put the original wheel back on the front left and the vibration at 45 MPH came back, so I'm 99% sure it's the wheel or tire. I'm taking my silver set of Style 95s to Prince tomorrow to have them checked out and straightened if needed. Then, I'll have my tire shop swap the tires that are on the gray wheels to the silver ones. I might eventually get the gray ones checked out as well, but only to sell them. From now on I'll have silver 95s again, well, at least until I find a better set of wheels I like, LOL.
I also just tonight got my bi-xenons installed in the car. Another pain in the *** like the wagon having to cut the lenses off, but went a bit better since the housings weren't as brittle as the wagon's were. Once the lenses were removed and all remaining plastic bits, installation is pretty easy and this time I used the butyl cord I had. On the first one, I used a bit more than I needed and it made it much more difficult to get it clipped, but adding heat eventually got it. On the other one, I stretched the cord a bit, making it thinner, and this went much easier. I still used heat and I found it helped to use the channel locks from the BMW toolkit to squeeze the lens to the housing.
I'm not sure I have the aim completely right, but since the height adjustment on the passenger side light wasn't broken, I aimed the height of the driver side on to it, then did the passenger side light and aimed it to the driver side. The light on the road is a lot lower than on my wagon, so maybe I have my wagon aimed way too high. I'll look up some aiming guides and see if I can get them better. For now, I'm really happy with the light output. I realized that on my wagon, I'm not using the 5000K bulbs I thought I was, but instead the stock 4300K bulbs that came with the car. I think they actually might look a bit better than the 5000K bulbs I put in the M5. Maybe I'll dig out my stock 4300Ks from that car and throw them in.
Here's a shot from my garage:
I'll take some outside shots tomorrow, which will look much better.