I use these and swear by them. they have saved me and other people around the track countless times
http://www.amazon.com/Alden-8430P-GR.../dp/B000H6PM32
i use them in my little ryobi drill that i use on my car normally. they run in reverse. one side drills out a small hole, and the other side has reverse spiral with notches in it that locks in and grabs the screw.
i can get almost anything with these. from the tiny set screws in CVD's to the large motor mount bolts.
before you get out the dremel and start cutting up your chassis, try these out first. you wont be disapointed. i linked them to amazon, but i think you can get these pretty much anywhere. i got mine at Lowes.