I have it and the alignment tool in hand and will measure and count the splines.

Anyone have an old X5 clutch laying around and can measure? It'd be pretty cool if they're the same. 550 disc with X5 pressure plate would be great on this car and great on most of the three series.

The 550 fits many of the three series. Really as far as I have found so far pretty much all the clutches are interchangeable. But I don't know, you never really know. I doubt they all are interchangeable.

Back of the valve cover looks clean unfortunately. The oil pan is seeping, it looks like the o-ring for the half shaft bracket may also be seeping, and that little inspection port for the flywheel, the cover is missing and unfortunately it's wet in there and there's a drop a fresh oil on one of those small hex heads for the rear main cover. Not 100% though I cleaned everything and it's only one tiny drop overnight. I have to check again it'll take a few more days to be sure.

Tonight I have the sunroof cassette on the workbench trying to figure this damn thing out.

Oh and by the way that reinforcement plate with the nuts is a pain in the ass. The f30 those nuts are just captive welded to the subframe so you just gun the bolts in and out in 2 seconds. This is a royal pain in the ass getting a wrench in there. I couldn't find any other way to do it on the ground apart from pulling the wheel off. I don't know how to weld yet but I would like to weld an appropriate nut on there and get a high grade bolt.