A 4lb engineers hammer works beautifully…
Eh… So on the 99-04 years, the buzzer was an independent device under the dash that you could simply unplug. On your 06, it’s a component part of the PSDM board (the circuit board with all the fuses on it). Disconnecting it would require desoldering of the component. Best bet for simplicity if you don’t have the tools or experience with that is to gag it. You’ll have to take the dash apart and look on the board for a black cylinder about the diameter of a dime and about 1/2" tall with a hole in the top. Find it and put a piece or two of foam tape over the hole.
Or, there is that hammer…