Fleece performance "all on " module...$20
Pull the light fuses in the box, place formed module in the tray like a puzzle piece, place fuses back in and voila.... hit the brights and you have hi,low, and fog going... turn it off and it gos to regular low light with normal fog operation from the dash...
20 bucks for 'super brights'...
http://fleeceperformance.com/electronics/gm-all-lights-on/gm-all-lights-on-module.html
You could also do the diode trick for a 4 hi (low-hi) for $1 from radio shack..
Eta: sav a deer whistles if you live in the countryside myself.. people say they don't work but when I drive by my little nighttime friends, that I occasionally hit before purchase, their ears are perked to the sky and they don't move a muscle... a .380 handles the problem, but it's frowned upon, like ************ on a plane.
$6 for 2 pack, and maybe saving a totaled vehicle...