Scott,

The front sway bar on mine is a little under 7/8", say 109/128".  No rear
sway bar.

I'd say the additional rear swar bar would assist the front one and give you
less body roll.  It would take care of the rear sway torquing up to the
front one.  I'm not an expert, but it seems like just adding the rear one
will have a big impact on body roll.  I'd add the rear one first, and then
go from there.