Hey Leavenworth Ks...I grew up not far from you....St. Joseph, Mo....been to Leavenworth many many times.....You Army?
Anyway locktite the night before might not do you much good...check your locktite instructions some say 24 hrs drying time.....and the heat will break it down
try a spilt style lockwasher.....I have an OS 1.60 with a Pitts style muffler no matter what I did that muffler would eventually lossen.... until I drilled a hole in the head of the screws and safety wired the bolts....
If you don't know what I mean by safety wire...look it up on the net or go to an airport and ask a mechanic to show you...thats easier than trying to explain it...basically safety wire you run a wire through the bolt heads to prevent the bolts from lossening
Good Luck