I watched that guy's great videos. Very interesting and impressive. I even bought the full rebuild kit (brushes, slip rings, bearings) from him on eBay. Ships from Ireland, so not good if you are in a rush. I think I did a quick VR swap when my alternator failed, and then bought his kit, and then when I had the engine apart later, it was convenient, so I did the rebuild.

Actually, looking through the video just now, I'll say that the back cover, etc. all look completely different vs. what mine does. Once you get deeper in there for the rebuild, everything he says applies, and the video is good. Apparently Valeo used the same brushes and slip rings on every alternator they made for about 3 decades (don't quote me on that, but I wish other manufacturers did not reinvent the wheel as much as they do).

And I won't doubt that *you* can do it in-situ, and if I really needed to do it to win a bet, I could probably do it too. But given a choice, and knowing what I know so far, I would remove the alternator.

On the tightness of the alternator when reinstalling, I've just cleaned up all the surfaces, and use anti-seize on a few key spots, and have never found it to be a big problem - e.g., no machining required. But I'll also say that probably due to being in California, I tend to have a lot less corrosion on everything vs. most of the photos I see of other engines.

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2001 X5 3.0i, 203k miles, AT, owned since 2014