Well...looks like the Minnesota farm boy showed the city-slicker once again how it's done...
I used a small drain auger and pulled the dirt out little-by-little. Took awhile, but it worked. After I was done, I flushed with a hose from the "high end" to blow out any small rocks that might have been left behind. Thanks again for the assistance!
Here are pics of the layout to demonstrate the situation:
Conduit runs from Bldg. to Bldg. One end was identifiable, other end was buried.
Buried end (Bldg. 1) filled with dirt.
Dirt gone, box installed.
Conduit run the remaining distance to the demarc.
The canal behind the building. Anyone/everyone who saw me working back there had to remind me that an alligator lived in the canal and to be careful...one eye on my work, one eye on the canal.