The negatives arrived a few days ago, and I finally had time to scan them. The detail wasn't as good as I'd hoped, but they have a good tone range.
I already had a print of this photo, which has slightly better detail but not as much tonal range. It's amazing how close the spot is to where Steve's uncle took his photos. It's clearly not exactly the same spot, but very close. It even looks like the same time - the weeds look the same. It's possible that two two photographers were standing or kneeling next to each other.
Steve: Was your uncle Basil's last name "Headford" (so I can properly attribute the source)?