There are at least 3 different 3068 Head versions that we identify for parts. We stock ome parts but because this Tripod has at least 8 versions that can be nearly 40 years old we cannot supprt all versions. The differences are Center Coumn, Elevation Crank, and Leg Brace.
Version 4 and earlier have a round center column tube, and the Main Casting to match. Version 7 and later use a six-sided Center Column and Main Casting to match.
The Main Castings for Version 7 and later for sure use a six-sided Center Column. These are not compatible with earlier versions.
Ealier Versions use an Elevation Crank that has a direct drive to the Center Column. The Versions 7 and later use a Elevatin Crank that engages a gear that lifts the Center Column.