Rocket 3 GT Exhaust Mod from Meerkat!!!!

Has anyone tried cutting the top or bottom off the stock box and removing the cat substrate, but leaving the plumbing in place? I've done similar with other bikes and I've noticed the empty chamber can give the modified exhaust a deeper note. Also, I think the reason a lot of people feel they have to run rich A/F all the time is because the shortened exhaust track of all the aftermarket exhausts causes the stock O2 sensor to malfunction, leading to the deactivation of a VERY helpful sensor. Not sure if the Meerkat mod leaves enough length for the O2 to operate properly? If no one has done it, can anyone who has done the Meerkat recommend where to cut to remove the substrate?