1942 Remington 1903 bolt question

Hi, my rifle is number 3078610, last day march 1942.
I believe the Remington 1903 bolt i need generally appears smooth where as a 03 bolt has several machined low spots. When this was changed i do not know.
I have seen photos of early R marked safety levers with both sides marked with serif style, and later marked sarif/block with weep hole and have heard tale of a sirif/block without weep hole. don't know what fits my rifle date.
I have seen R marked extractors with gas port hole on early models, but I don't know if this was changed and when.
Don't know which firing pin type for my date early, mid, late?

Any thoughts would be helpful
thanks scott