What he said: 16ga (.063" dia) and 1/4" ID for links. 12ga and 1/2" is huge and coarse. You might unload it on a LARP-er with no taste in mail. I'm only half kidding.
With the Creative Anachronists who hit each other hard with rattan sticks, three habitual link sizes occur in steel: 14ga @ 3/8", 14ga @ 5/16" and 16ga and 1/4". All three are convenient; the Armor Standards do not address mail.
My plan was to do a top dowel with the byzantine off the bottom, but working the "wrong" way is just throwing my mind for a loop every time I have tried it. I will try again tonight once the kids are in bed, if I can't get it, I will keep working the "right" way and figure out the rest once it is done.
I did my first Beast last year, in 7h45min. But I was not worried about time, just wanted to finish. Being a prairie boy, going up the side of a mountain was something very new. This year I hope to cut an 45-60min of that time, now that I know what to expect. I also might try a stadium Sprint this year.
If you're planning on hanging the byzantine off of a frame (like the one shown above), "right" and "wrong" ways won't matter for hanging the byzantine chains.
If your're hanging the inlay between two dowels, "right" way is likely to require more rings than "wrong" way, as the inlay is going to want to squish together under its own weight, making for more rectangular "pixels" in the image.
If you're planning on just having a top dowel and hanging the byzantine off of the inlay itself (which sounds like your intent), you would probably be better off using the "wrong" way hang. I have some patches of Euro 4-1 and various chains around the house. I see what I can mock up and take some pictures of the curl in either direction.
I ran my first Super Spartan (8+ miles) in 2012. I still fear the Beast (13+ miles). Congrats on doing Trifectas!
it (obviously) depends on how much you need to "stretch" it at the top for how much it tapers at the bottom. i've just taken to make supports on the sides too, so i can adjust it as much as i need to, e.g.: