Expose Fretboard Diagram position in inspector

In their simplest ("cowboy chord") use, each Fretboard Diagram represents single named chords at a fixed position. However, more advanced uses rely on movable chords, which change their names based on the fret used. Fret position is changed today by using a slider on the "Fretboard Diagram Properties" popup. It would save considerable notation time if the inspector allowed direct modification of the fret position, without opening the popup. Then a single palette entry (e.g. M6root6 -- major 6th with root on 6th string) could easily be used in any key.