Expect a one-hour labor charge or whatever your dealership's minimum diagnostic charge is. They won't just reset the light without verifying the coded fault is no longer present (and rightfully so, this being a critical safety system). Ask me how I know and how I know the Bentley manual was wrong. There will be no problems with the airbag light provided all components are properly connected when you apply power. To adjust the new regulator, you have to cycle the window once through its full range of motion with the regulator attachment bolts installed but loose (to allow movement), then torque them. This of course requires reconnecting the battery and turning the key to the accessory-power position. The Bentley manual describes the procedure but does not (in my edition, anyway) include any cautionary note regarding the disconnected airbag. If you overshoot "accessory" (P1) and hit "run/on" (P2), it triggers the airbag light. To adjust the regulator, it's a good precaution to temporarily reinstall and reconnect the airbag, then the battery, perform the adjustment, disconnect the battery, then remove the airbag again and proceed with reassembly. I do not recommend tying up the airbag to avoid disconnecting it, as I mentioned earlier. It puts undue strain on the harness and connector. While it arguably does no harm, I regard it as foolish impatience to mistreat an explosive device on which someone's life may someday depend, merely to save ten minutes on a two-hour job. The plastic push-clips are replaceable on both E46 and E36 door panels. They're under a buck apiece but usually survive being removed once or twice. Just don't be hamfisted about popping the panel off the door.
