what i would do is rally another v3 (i have one i'd spare for this), and go:
_V3 #2 (oade mod, attenuated)
/
v3 #1 (preamp and analog out)>--
\_v3 #3 (stock, attenuated)
doug acm'd one of my v3's, and i promised him i'd get some comps up, but have never had the ability to... until now....