What is the alternator clock position on a late 1986 corvette?

There's no standard "clock position" designation for an alternator on a 1986 Corvette (or any car, for that matter). The alternator's location is relative to the engine and other components. A picture or a diagram would be needed to describe its position accurately. Even then, it would be more useful to describe it in terms of its mounting location (e.g., "mounted on the passenger side of the engine block, near the front") rather than a vague clock analogy.