"W. McClelland" is shown in three locations on the 1868 Beers Atlas.The first is on the SE corner of what is now State route 895 and Wedgewood Road(a couple of miles NW of Newark DE).From there, if you go east on Wedgewood about 3/4 miles (you'd be in Walter Carpenter State Park), there is a small, probably dirt, road to the left.About 100 yards before that intersection is a house on the south side of the road labeled "W McC" which is probably a McClelland. On the NW corner of that intersection is a clearly marked W McClelland house.
All of these structures also show on the 1898 Baists Atlas.The first does not show the owner, but both of the others show belonging to a Wm Coyle with a notation of "95 ac" presumably acres.
None of the structures show on modern US Geological Survey topographic maps.Go to the following link to view a USGS map of the area:
An aerial photo does show a structure where the first house would have been.Can't tell if it's that old, but it would not be unusual to have a 150/200 year old house still standing in that area of Delaware.The photo shows the location of the other two structures to be wooded, so it wouldn't surprise me that you could find traces of them if you went and poked around.See the following link for the aerials: