Thanks Kerry. I get it now. FWIW, in my non-analog capacity I shoot a lot of stitched panoramas so the importance of a level platform is understood.

When I asked earlier about it going under a tripod head, I was alluding to mounting either a panning base or a ball head with an incorporated panning base to the leveling head.

Are the ballheads' balls marked in any way so that the neutral, vertical position can be found quickly?