This is probably overkill, but considering I purchased a titanium exhaust, which has caused problems for people due to heat, and I really didn't want to hassle with repurchases or reinstallations, I did the following:
1) I used Permatex "The Right Stuff" Red around the electrical component where the wire comes out of the Milltek Controller. This stuff was a little difficult and messy to deal with and requires some care.
2) I used the E6000 which was included with the enclosure to seal the rest of the enclosure because it's much easier to apply.
3) Then I used high temperature wire loom over the wires.
4) Finally, used Design Engineering Cool Tape (claims protection up to 2000 degrees F).
Here are some pics. I'll let you know when it explodes....