So, finally got to crack it open. Battery tray is still in but loose and we loosened the locknut on the right throttle cable so it's still attached to the bowden but free of it's holder. I didn't have any problem with unplugging things from the wiring harness, although we did end up pulling the starter. As an aside, I have a lot of work to do repairing damage to the harness by the factory zip ties -WTF was BMW thinking with those? I was able to get the entire drivetrain off from the transmission back with the help of a friend. I fashioned three guide pins out of 100mm M8 bolts by cutting the heads off and notching them for a standard screwdriver. We pulled the clutch slave first which allowed us to pull the pushrod back so it easily cleared the splines. Then we used a rubber mallet to drive the transmission back before finally balancing it on a couple of jack stands.
The splines look great even after ~40k miles without any attention so I thankfully seem to have a properly-shimmed gearbox. The clutch slave puked though, but it seems like we got to it in time before the hydraulic fluid entered the clutch housing so maybe that felt ring actually did its job. I can't definitively say that the transmission shaft seal is good yet though...way too much engine oil and grease all over the entire clutch housing. I already have the rebuild kit on-hand for the slave cylinder and I will be ordering up clutch parts soon, including an aftermarket friction plate from the Boneyard (not the oil-resistant one, but this one
http://www.beemerboneyard.com/2123454bp.html -it's ~$70 cheaper than OEM).
The fluid that was in the clutch slave housing looked pretty clear but does anyone know if there is any way to tell whether the transmission input shaft seal is still good?
I promised pics, so here are a few hi-res versions. In order, they are: drivetrain, input shaft seal, input shaft splines, clutch slave housing.
http://www.tc.umn.edu/~ehoover/images/IMG_0868.jpg
http://www.tc.umn.edu/~ehoover/images/IMG_0870.jpg
http://www.tc.umn.edu/~ehoover/images/IMG_0871.jpg
http://www.tc.umn.edu/~ehoover/images/IMG_0874.jpg
and clearance to get the gearbox/s-arm/ hub assembly out past it.
