Hi. You specifically mentioned the 1860-1865 period. An excellent resource for just a few years later is the
Beers Atlas maps, made in 1868, that show each Hundred in the State of
Delaware, on individual maps. These maps indicate who all the land owners were, and you can see proximity of properties (or at least of land owners) to one another. While a map such as this may not help you with the precise span of years that you asked about, the Dagsborough Hundred map from that
Beers Atlas map series may very well show some of what you want to know. This resource could easily come in very handy if you already know who some related, and/or neighbouring, families were, as hopefully at least some of them would appear on the map. The
Beers Atlas maps are available from the
Delaware State Archives. They'll gladly make and mail you photocopies (for a copying and mailing charge, of course).
Hoping this suggestion will prove of some help.
Best regards,
Dave
Wilson