Hi Shel,
In Hunt's 2nd book Randall Military Models, he publishes some letters in Chapter 8. On page 287 is a letter from Bo to a collector talking about identifying early fighters:
We at the shop can fairly well tell the differences between the current Models # 1, 2 & 3. The changes are subtle and none too prominent, so an ordinary person would have a hard time of it and we (The shop) can only guess within 5-8 years. The very first 1's and 2's, made almost 100% by myself, are recognizable by the unusual bent brass with hole drilled that I had to use for attaching the wrist thing. There are not that many of these around.
Given that Bo started shipping fighters in late '42, I think it's reasonable to assume that the terms "very first" and "not many of these around" would preclude all fighters shipped in 1943 having these links. We also know that Bo didn't make almost all the fighters shipped in 1943 by himself. The sheath "looks" like a Southern Saddlery as opposed to a Heiser or a Moore. If this is the case, then the wrist thong links continued at least into June of '43 as this is when the 1st SS sheaths started coming in. Please note:
1. Although Bo specifically mentions "brass", some percentage of these wrist thing links were made of steel.
2. I mentioned in my previous post that this sheath was set up for the long narrow Lily White Washita. As you know, this stone transitioned to the Norton Soft Arkansas. I have seen fighters with wrist thong links in sheaths set up for the Soft Arkansas, but I've never seen a '44 documented fighter in a sheath set up for the Lily White.
Best,