12v Power Source Behind Dash???

I need to install a switch in my dashboard and hook it up to a 12v Auxilary power source in a 98 Tahoe I took the dash off this weekend to look for one, but I am clueless and thought it best to get some input before I did anything stupid. Any suggestions/ knowlege on this would be great. The switch is for an electric cut-out I welded on my exhaust on saturday. I cannot wait to hear how it sounds!!

i dont think there is one, i needed a 12v for my gauges, but couldnt find any, you could either A) bum it off of the stereo's power, or B) (what i did) run a line from the battery to where ever you need it (make sure to put a fuse through the line)

Thanks for the reply Shield. When you say bum it off the stereo do you mean just connect it to the same Aux Power wires running into the stereo or are there any Aux Pwr Out plugs? I have a kenwood replacing the original stereo. Also, if I ran it from the batery where would i connect the wires to the battery? Im assuming I would just run it through the firewall on the driver's side and up into the dash. What kind of wire would I need to buy?

Thanks

i meant by bum, u could strip the plastic off part of the power wire running into the head unit (before the adapter), i have a aftermarket battery where it connects on the side (rather than top mount), i assumed all hoe's were like that, if not u can always run a wire around and put the car battery power connector over the wire so it makes a snug fit, if u do have the connectors on the side, i got an O ring type connector (can typically be found in wire connector packs), and put it between the connector for the car and the battery. I ran the power w/ some speaker wire, but made sure to put a inline fuse somewhere (right past the battery for me) just incase something accidentally happened. If you need any questions, or want me to take pictures of it let me know

Thanks again for the reply shield. This time I think I've got the idea. Pictures of your work would be great if you've got em. Just e-mail them to wbseeley@hotmail.com. I am swamped with work all this week and then leave for a week on vacation so I wont get around to the wiring for at least a week or so, but when I do I will be sure and let you know how it turned out. Thanks for the help!