Funny thing here is that I'm an OEM guy. I've had many BMWs and they've always been OEM. From 3 series to 7 series and 3 M-cars. Never switched "wrong" parts to them, not even rims. Always BMW original and parts meant for that car. When buying cars, never looked to ones that have been modified in any way.
I know the feeling when I see something off spec and probably horribly modified too. But I'm not going to them and saying that "hey you're doing it wrong...". That's just the way they like it.
My starting point was to do an electric conversion of some car, just for the learning and fun of it. I did not have E9 in mind at that point, but as I love BMWs I quickly ended up looking older BMWs ending up to the prettiest of them all, an E9. So I kinda had to leave my OEM boat even before buying the car.
I have huge respect for you guys who keep it OEM but also for the guys who are doing as they wish. Engine swaps, interior mods etc. After all, this is a hobby, not a religion.