A 98% 1917 with that low a SN? Sounds almost too good to be true, please post pictures. As to the pencilled SN, the pencil marking does fade and often can't be seen without using bright light and holding the grip at an angle. I've sometimes been able to make them out in sunlight and sometimes with a bright flashlight and magnifying glass. Sometimes you can see that there had been numbers but they are no longer legible, or not all of them are. Good luck and we are EAGER to see pictures.

Jeff
SWCA #1457