Those mufflers and resonators are tuned to eliminate the resonance on the engines when they go into MultiDisplacement mode, and also for a V* that has no heat crossover in the intake manifold. 2 features our cars don't have.
I have an X-pipe setup on my sig-pic car, and when I blocked the crossover in the intake I got an *awful* resonance that came on/off like a light switch at particular RPM (no tach, unfortunately) and that spot was 1/2-way between idle and a normal shift point. I drove 1 block that way, turned around and unblocked it.
I'm not saying you'll have trouble, just that resonances can be a funny thing. Maybe the mufflers by themselves will be OK - let us know!
Do pre- and post- soundclips!