Another ghost story. The “ghost” is also from the Revolutionary War. The ghost was murdered for some reason and his body hidden (in a well, I think). He befriends a human modern-day boy and together they solve the mystery of the ghost’s demise.
Stump the Bookseller
New format, same book stumper solving.
The Ghost Belonged to Me by Richard Peck?
That’s definitely The Ghost of Dibble Hollow! I don’t remember the author, but you should be able to find it online.