Oh great, this is an awesome post!!!
I too have the stupid hvac dial issue and the darn whistle.

Im' going to pull the neg connection out. Is this right off the battery?

thanks,
H

Yea, it is a blast to get too as well. Just pull the stuff out of the rear-end and I suppose if you don't have air suspension etc then it is pretty straight forward. I left mine off while I did a bunch of other stuff (maybe an hour or two).

Good luck and please report back.

ok, awesome
I believe i do have rear air suspension, this will be done over the weekend anyways.

So pull the black cover off under the spare and disconnect the negative cable for an hour plus. Sounds like a plan.

Any surprise resets or calibration that I have to perform once the car is back alive?

Nope. My alarm gave me a single chirp when I reconnected it and that was it. My radio settings even stayed. Weird. I felt like a moron taking the time to get my settings on paper to reset them, and my wife got a good chuckle out of my reaction when I went to readjust the audio, haha.

Sweet, thanks!

I will be trying that!. Now what about the HVAC dial in the middle.
Does it still retract back and not cooperate?

It seems to be ok now. I chaulk it up to a stuck flap, but then again I have to fist-fight my wife to be able to drive it (I bought it to replace her car). I will check this weekend to confirm that it is still good.