You're welcome, I spent about an hour perusing EVERYTHING under stainless steel at McM. The .083 wall is a little thicker than necessary, but not hugely so.... I've been looking for something like this. Checked M-C but somehow missed this one.
Drill 4 holes in the flange at each quadrant, drill a hole in the firewall larger than the tube OD, insert the fitting thru the firewall, match drill (transfer) the holes in the flange to the firewall, and fasten in place with SS rivets or small stainless screws. Use the same fireseal goop that everybody uses. Use firesleeve to wrap the wire bundle and seal it up good with hoseclamps. At least one of the vendors for these has a tutorial on how to do this online.Forgive me if this is a silly question:
How do you secure that to the firewall?