Posted for randy snarr <randylsnarr@yahoo.com>:

 Jay,
 I just drilled out the hole the size I needed.  Start
 small and increase the bit size slowly. That helps
 punch through the Stainless Steel. Once I could get my
 Dremel drum sander in the hole I used that tool to get
 it to the right size. I burned several drums in the
 process.
 I then used a piece of fiberglass tube and bonded a
 1 " length into the hole (tight fit) with high temp
 RTV. I used the hole to pass many connections through
 the firewall during const and when I was done I filled
 up both ends with more high temp RTV. I have since had
 to pick out some of the RTV to run another wire. You
 simply RTV the thing back up. Neat, cheap and easy to
 do... You can also make a stainless patch and screw it
 to the firewall to cover most of the hole to help keep
 the fire out.
 I am certain there are more sophisticated ways to do
 this but this worked great for me and if you do it
 right it looks nice....
 Hope that helps...
 
 Randy L. Snarr
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