Randy,
I did this on my 92 400e, and it was a snap. Took less than an hour. I removed the old one and started at the computer and worked my way forward. I think you will need an allen socket for the harness bracket where it bolts to the passenger side cam cover. The MAF will need to come out, and so I'd make sure to have a new rubber boot, as when I did mine it broke, and I had to duct tape it together until the dealer was open again. THe boot I'm referring to is what holds the MAF to the throttle body.