There shouldn't be any "wiggle" with the DIAS and if you look at an M-16 with the GI sear and the location of the GI sear that is critical for the function of the M-16 as well.
You stick the timing gauge in the ejection port I believe believe...
I don't have any photos to share as I don't have a DIAS or M-16 that I could show you with and frankly the advise on that page came from other people as well (RE
http://quarterbore.com/nfa/dias.html).
I see now that there are no credits on that page... I believe that is because the preson that provided it didn't want credit...
Anyways, I am not sure why this sounds confusing and if I get a chance I might be able to show you how to do this using my rLL as I assume the LL should time about the same...
Anybody else have any advise on this?