Would a fused disconnect for a transformer fall under 110.26(E), all switchboards, switchgear, panelboards, and motor control centers... There is part of a drain line 5' above this disco.
This is not a "working space" question. It is a "dedicated equipment space" question. And the answer is that if you are dealing with something other than the four items listed in the article (the same ones you listed), then the article does not apply.