Bass note under the Chord Name Symbol

I have a requirement to print the name of the bass note under the chord symbol separated by a line rather than beside it separated by a slash. "F/G" is what Lilypond prints.  What I need is F -- G I've searched the docs, the user groups, and sample code, but can't find a way to do this.  Any s

Re: Musica ficta

scheme guides I've used (found with a search engine): http://www.cs.hut.fi/Studies/T-93.210/schemetutorial/schemetutorial.html scheme tutorial by Catharina Candolin [clearly laid out] http://www.ccs.neu.edu/home/dorai/t-y-scheme/t-y-scheme.html teach yourself scheme in fixnum days [