- I tries using 1/16" cobalt bits to drill into the stainless of the stainless steel lower firewall, but the bit broke almos immediately.
- So I bought a 1/4" spade bit at the hardware store. It had a pointy tip that I drove into the stainless with a hammer. It left a small linear hole in the metal, which was enough for the drill bit to bite into. I FINALLY got all the holes in the lower and upper firewall stainless done! What a pain in the butt! As it turns out, my jobber bits worked better than the cobalt bits once that starter hole was there. And using cutting fluid made things worse. Apparently it was TOO slippery, causing the bit to slip, rather than bite.
- Next I bent the stainless steel fuel filler box (photo #1) in my brake.
- Then I used a $6 pair of nibblers to cut out the fuel filler opening in the upper firewall (photo #2).
