I unpacked the "new" E39/46 M Sport steering wheel and installed it this am. I need to revisit it as it is about 15 deg. off center, but that should be easy(er), now that I know what I'm doing. Very much plug and play, as mentioned by Clavurion, and really only one question mark remaining. Thanks for the advice and leads.
Nothing too cosmic: the airbag plug fits the plug in the steering column, but is a different profile and therefore doesn't lock into the female end. No codes though on my test drive, so I'm happy the ebay bag I picked up is working. I'll do some more research on the subject and see if there is another harness for inside the steering column that BMW used for the M sport wheels. I didn't pull the column clamshell cover pieces to investigate yet as I figured I'd research on Real OEM first. It could be that the appropriate female end is pre-wired in the column, just waiting to be plugged in. Its all working fine, so I'm happy to do some research first.
The Ebay seller is "Markoparts" and the wheel was packed extremely well: a zillion layers of plastic wrap, then bubble wrapped inside the box.
The craftsmanship is really very nice. All the stitching and seams are very tight, very nice leather and the small lower portion is done in Alacantara with no glue bubbles, etc.
The old wheel comes off easily after removing the negative battery terminal. Two T30s on the back release the airbag and both the airbag and multifunction harnesses plug into the column at the 12 o'clock position.
After that the center bolt comes off and the wheel pulls off easily. There are guide pins on the column that fit into holes on the back of the wheel so I popped it onto the column in what seemed like the only way possible. Hopefully though they allow enough movement to reclock the wheel the roughly 15 degrees I need...or I'll need to make some slop in the wheel holes. You can see the yellow and white plugs at the top of the wheel cavity, which plug into the column behind them. The yellow (airbag) plug's shape is different than the plug that was on the OE "comfort" wheel, but plugged in fine. It doesn't lock in however, as the OE wheel's plug did.
You can make out the different plug size in the pic below after I plugged them in.
After plugging the two plugs into the airbag, it pops right into the wheel with some pressure. No screws on this one, but rather it is held in by springs which engage two notched tabs on the airbag. Push the tabs through the springs and they engage the tabs and lock the bag in. I think it comes off with a screwdriver from the back, which will spread the springs and allow the airbag to be pulled out. I'll find out this afternoon when I work on reclocking the wheel. Hopefully I can do it without disconnecting the bag as I don't want to pull my trunk apart again to disconnect the negative terminal.
Pic of the back of the post-recall airbag I got from ebay.
After reading and resetting all the power interruption codes, my airbag light came right back on during my test drive. The foxwell told me that thankfully it was still on, like it has been for 8 months, due to my long term right front door side airbag problem. I've got a new airbag in route from getbmwparts.com to hopefully fix this.
Very pleased with the way it looks, and that all the buttons, horn, etc. work as well and that I don't seem to have awakened (yet) the BMW gremlin that occasionally appears and makes trouble on what should be easy jobs.