Well, I'm near the max strap length (one more set of holes to go) and this is what I have so far. Like I said, I'm probably a tad larger than the average WWI soldier.
I had to remove one end of the strap and reverse the mag pouch to get it oriented with the flap up when on my chest and hanging as shown.
The metal plate on the strap is the what is keeping me from using the last set of holes and extending the strap as far as possible. I tried to snip the rivets holding the plate with a wire cutter last night but they are too tight and hard. I'll likely (carefully) use a grinder to do it.