... I think I figured something out, but it's tedious and ugly. I'm not sure it'll update parametrically if something in the model changes without causing some weird quirks on the drawing sheet.
Highlight Dim
Right Click, Properties
Terminator and Symbol tab, Set Display Both, Measurement Type Double arrow, Origin Type Arrow
Lines and Coordinates Tab, set Projection Line Display: Origin (omits the measurement end)
You will have to manually move the extension lines after placing the dimension with the origin at the feature edge in the detail view, and measured end at the feature edge in the main view. Basically, keep track of where you click first and second, first click is origin and second click is measurement.
After deciphering the convention for all of that, this is the best I could come up with on my own. Is there an easier, possibly more reliable way to do the same thing?
Thanks!