Good eye -- a lot of people don't notice. Checking the mast length is an excellent way to verify full seating. I get 13 1/32" for the squared off masts installed. Your masts should fit in exactly the same but as you've noted, thread friction can vary. You can remove the Loctite Blue masts with a little effort. Clean the threads, blow out any debris and dry fit the masts to make sure everything is cleaned out before re-Loctiting them. They'll go in easier next time and you should be able to feel them seat once dry-fitted. If in doubt, you can mark the masts where they should break the surface to verify your depth or check the exposed length immediately. I tend to be generous with the Loctite, as it acts as a lube before it sets up (which is pretty fast).
Whenever installing new masts or sprockets it's best to dry fit first. This process cleans out any burrs and exposes in advance any tight fits.