Letting smoke out of the wires.

Just had the upholstery done in my 66 Barracuda. My upholsterer hooked the amp gauge wires up to those two posts below the oil pressure gauge instead of the two posts they are supposed to be hooked up to. I put the battery terminal back on and got in to the smell of smoke, thank god I didn't just hook up the battery and walk away.
What is your best guess on what might have fried? I took the dash out and can't see anything obvious. Also in my haste I broke a corner off the dash bezel, so if anybody has a spare...