While replacing the starter with an OEM reman, no ground wire was found on the bottom mount bolt as depicted in the FSM. Instead, there is what appears to be a ground near the top starter mount post (see picture). This possible ground, however, only appears to attach to a plastic clamp that rotates freely on the underlying sheathed cable bundle -- it has no actual further wire/connection to standard grounding points. Have no history from PO.

Has anyone seen this? Where should the ground wire be located?

 

That's not a ground, as far as I can see. That is a support for the wiring harness. The starter can be grounded through the engine, and a separate ground wire can be put elsewhere. Starter may have been replaced in the past and someone moved the ground wire to another bolt on the engine or head maybe, or it can even come from the factory attached to a different place.