Desert Dagger changes over time?

[ABTOMAT-47]

Question for the SOG collectors: Anyone familiar with slight changes to the Desert Dagger over the course of its history? I have two that are almost completely identical in appearance, manufacturing, markings, etc, except a 1/4" difference in blade length and a tiny different in width. One's 6.5" long vs slightly under 6.75" for the long one. Looking at old catalogs the published spec was 6.5" early on and 6.25" later. Did they actually make them shorter at a certain point?

Short one isn't reground--it has the original "big" style kydex sheath that's 1/4" too short for the longer knife, and the longer knife has even been resharpened. Don't have the sheath for the longer one so I can't say what era it's from. The longer knife has a slightly more polished finish (as in possibly finished with a finer grit or maybe a buff) but that one's also been used so an owner could have done that.

Mainly curious which one is older. Gonna have to be careful looking for replacement sheaths if they're different sizes.

 

[Ruari]

I think those changes are likely subtleties from the manufacturing processes, the only big variation (aside from sheaths) I can think off was a limited edition stacked leather handle version.
Perhaps an easier way will be to check the marking on the ricasso, specifically the address, which would give you a better idea of the date range of production.
Some resources to older SOG knives are here:

https://onlysog.com/product/desert-dagger-s25/

And here

http://www.sogknivescollectors.com/desert-dagger-s25.php