I spent a few hours today looking through 3rd Edition of Joe Poyer's 1903 book with the rifle in front of me. This rifle is still looking very correct. Seems to be what is referred to as: 1903 .30-M1903 Knife Bayonet altered to .30M1906 with M1905 Sights (2nd Alteration), Springfield.

Apparently the K marked in the Mag Cut Off area means that that stock was made by Keystone.

Rear sight, slide, drift slide and sight leaf, front sight, "S" stock with the JFC, Type 4 handguard, both barrel bands, type 1 mag cut off, 1st variation bolt, all appear to be correct for a 1908 rifle.

One thing I am a little confused about is the reference to the front sight base being pinned in front or rear. The only pin that is visible is the one holding the sight leaf on. The front of the sight has a slotted screw toward the bottom and the rear has a square hole. Is the screw hiding another pin?