Someone else mentioned adding another line atop the treble clef and then using the 6-line staff for both clefs. I like this idea because it maintains the one-line gap between the staves and also somewhat reduces the need for ledger lines, which drive me a bit mad.

hmm... i'm confused... 8vb is for lowering an octave. the proposal here is to make both clefs have EGBDFA. ie, the clefs are off by a third - this slides by a 3rd to make them have the same arrangement. ah, actually i think i got what you're saying: ie, just use 8vb and use treble for both. sure that'll work too, tho the A below middle C is kind of popular :), otherwise it'll have to be constantly dotted lined in.