ORIGINAL: smkrcflyer
Im going to try the Treaded 6-32 rod & 2 6-32 Lock Nuts.
Do yourself a favor, and clean it good, and assemble it with some HIGH TEMP RTV (silocone). It should stay together forever, and not rotate than. You can get "Aluminum colored" which you canot even see when it is applied.

This is a trick that is used on Tower Hobbies mufflers to keep them together.