When you turn on the a/c does the a/c work? The Compressor clutch engage when the a/c is turned on? What about the little light on the a/c button? Does it come on when you push it and what does it do whenever the gauge fuse blows? Stay lite or go out also? What I am getting at is possibly the light behind the a/c button is shorted out, causing the gauge fuse to blow due to the excess current flowing. Just a guess. I have a wiring diagram on my other computer. I will look at it when I can access it.