I was installing my Isspro pyrometer this weekend and I got everything hooked up except the ground and power wires for the circuit box/amplifier. It says to tie the power wire into a fuse which only comes on when the key is turned over. I have narrowed it down that the only fuses that come on when the key is turned over is the fuses in the fuse box inside the cab. Does anybody know which fuse I should tap the wire into?? There is a spare spot where I can put a fuse and I thought about putting it right there....if so, what amp fuse should I use to put in there with it?? Thanks for the help guys!!!!