Next, I found an elderly Alkire Eharp Steel for sale here, and bought it. I'm waiting for it to get here, while also waiting for a 6 string pedal steel. Running off in all directions at once.
Anyway - while I wait, I've been playing with a spreadsheet of Eharp tuning. I've found 12 distinct chords, not counting both flavors of 7ths, at the "fret zero," no bar position.
The trick is that this is all done with unique grabs, while the pedal steel (particularly the full 10 or 12 string versions) accomplish this with relatively fewer different hand shapes / grabs, by changing tones through pedal and lever.
Anyway, if anyone is interested, here's a screenshot of what I've found so far, before even laying bar on fret.
