I agree also - you're off to a good start. Be sure to also check the dates for overpunched dates - fairly common on the Indians.
Couple ways to see examples - on Ebay search on "indian head overpunched", or "indian head RPD" and there are usually a few examples. Or to to indiancent.com and to the indian head category on the left, then look for coins that have a "Snow" attribution - many, but not all, of those are repunched dates. It's basically when you have one or more digits of the date that lie on top of each other. Some are easy to see, but a magnifier makes it a lot easier. This is an easier one to see: Some are not so easy to spot (note the bottom of the 1, and the bottom & right edge of the 9: If the coin has a lot of built up grime they may be impossible to see. I have a 700 page book of various overpunched dates & other attributions by Richard Snow. I have 7 or 8 of the Snow overpunched dates now, and have fun looking for them. Some I had in my collection without even knowing it, and others I can usually find at a good price where the seller isn't even aware of them. I have 3 different ones from 1907.
the 1864-L is a Snow 7 (S-7) 1907 is a Snow 10 (S-10) These are easy to spot too - an 1897 Snow 1 (S-1) called the "1 in neck" attribution (lousy over exposed picture I took):
