I understand. I guess my point is that it should be the dealers problem, not yours.
You can pull the four screws that hold the upper dash on and carefully lift it up while clearing it from the steering boot. You can't lift it very far though before you need to reach under and dis-connect the tach cable. Un-plug two plugs to the gauge assy and you can remove the entire upper dash.
From there, it will all be pretty clear as to what needs done to get the gauge housing out of the dash and take the cover off.
Hope that helps,
Ken