I've been dreaming of this setup for a long time.
Boss Line Selector -> M9 -> Custom blend wet/blend {loop: Full Tone Bass Drive } -> back to boss line selector
The line selector is so I can turn everything on and off. The custom blender allows me to blend my clean with the overdrive. The switch on the blend pedal changes between 100% wet and the blend between wet/dry.
I'm still looking to expand this setup but I'm extremely pleased at how well this works live.