Type II lockbar sight question

I'm hoping someone can answer a question I have about the introduction date of the Type II lockbar sights on SA weapons. I have a 8-42 barrel dated Garand on layaway at a local pawn shop. Serial number is 8258XX and as I mentioned in the big 5 thread, it appears all correct aside from a SA/GAW stock. This piece has Type II lockbar sights that appear original to the weapon and given that all the other parts are the original, un-modified correct early parts that match the Duff data sheet for this period, I'm thinking they are also original issue to this piece. Anybody know for sure when the Type II's started being installed?

Thanks in advance for any help or info,
Mike

Duff shows on his table 5.1 (page 191 of the "Red Book") the type II long pinion lock bar coming in at around December 1942. His data sheets have #1006586, November 1942 with a type I short pinion lock bar and #1020146, December 1942 with a type II long pinion lock bar.

Going off this information yours should have the "Holy Grail" of rear sights, the type I. That said, never say never, never say always!

If it matches, I wouldn't tinker with it. SA considered "Parts is Parts". Receivers were never assembled in numerical order.

Duff also states that "the engineering drawing of the new locking bar and long pinion is dated 14 Nov, 1942. A Field Service Modification Work Order was issued on 21 Jan. 1943 instructing that all rifles currently in service were to be changed to the new configuration. It is Duffs opinion that "production of new rifles with the long pinion most likely began in Dec. 1942, However, it could have begun as early as Nov. 1942 or as late as Jan. 1943."
It is possible that in compliance with the 21 Jan. 1943 Field Modification Work Order, the rear sight on your rifle was changed from Type 1 to Type 2.
That, of course would not have taken place in a combat area but could have been done at the unit level at just about any time prior to the introduction of the T105E1.
In my opinion, while there is always the chance, that for some unknown reason, your receiver had been set aside and not assembled for about 4 or 5 months, and ended up having a Type 2 installed, it is highly unlikely, especially considering the 8-42 barrel. If this happened then the Type 2 could be considered to be original to the rifle.
I guess to be considered 100% correct as it was when it left SA it would need a Type 1 short pinion.

That was the info I needed. I imagine now that when this piece got it's replacement SA/GAW stock, it probably recieved it's type II sight assy as well. At least they left everything else original. I have a restored 6-42 rifle with the correct type I sight, so this one won't bother me too much. I'll just leave it alone for what it is.
Thanks again, Mike

Mike, I would feel the same way you do. It is a part of the history of the rifle.