Some disjointed response comments from above, not necessarily in order.
A point of order on Winchester 70 "dating". First, that serialization number via best source "Polishing Room" data, may widely differ from he barrel date found in under stock breech area. "Barrel date" reflects when the barrel manufacture was completed. Assembled quickly or shelved for a decade or more! Factually some rare chambered Model 70 rifles with SNs in early Postwar and barrels dated prewar! An period known as "Barrel Cleanup era" as Winchester disposed of old prewar stock barrels creating legit "Factory new rifles!" such as my 55xxx SN Model 70 Carbine in 7mm.
Model 70 receivers were not built out in sequential order and may vary in terms of calendar year dating's to such as intro of chambering! I don't doubt there were factually some prewar dated receivers not built out until postwar too. The situation is "collector presumption" as being pretty rigid. We know for instance that the Factory did make custom accommodations such as D&T scope holes before production line reality. But collectors work on probability theory and simply disdain to accord a probability factor. If it's not of "known" production factory features", it's fatally "Non-original! Case closed & I agree with that! Credible "Provenance" the only exception... Maybe!
Custom "group orders" as documented such as the Gopher Shooter Supply "barrel sights delete" are such exceptions forming "Class" of variation.
Concerning blue, the dull blue prevailed in the late forties forward to my knowledge. Prior a deeper 'higher polish' blue but "Custom Shop plus... "Your experience may have varied." I'd check "The Good Book: Rifleman's rifle if I could just find it!
Varmint Guy: I intentionally stated "nineties era", reflecting when I acquired the rifle. Sorry if any lack of clarity and thanks for the opportunity for me to make clear.
I've added yet another question to a growing list "pending getting to my guns with time to review". Or fate what it is, my Estate, if to give a "S**t!
Thanks to all contributors here, I'ts been fun! Let's do it again soon! Just 'other subject perhaps!'
Best!
John