do you have the magnaflow catback or you just magnaflow mufflers? are they welded on or bolted on? if bolted take them off and drive with it and see what you think. i went the opposite route you went and removed the mufflers and kept the resonator. its not obnoxiously loud, but theyll hear you coming thats for sure. in 5yrs ive never been pulled over once for it being too loud, and i worked in pa. i think a cutout with no res is going to be a little bit of overkill, but thats just me. this only applies if were talking about ls4 cars. i think the 3.8 sounds better the quieter it gets. there was a guy with a gxp who got rid of the mufflers and replaced his resonator with one of these Classic Chambered Exhaust Inc. - Products
it sounded pretty tough.

 

wow thank you all for the info and suggestions. shows how stupid i am i thought i would need two cutouts. if i put it after the cat its worthless right? before the cat is the way to go? and monte man yes just the magnaflow muffs however they are welded on.

 

after the cat is still fine, it bypasses the res and mufflers

 

where are you located? I'm in WI, I have 15' of 304 Stainless pipe..

Also, I agree, cut-out only one is needed.. I actually have one of those too :p both are 2.5" let me know if you're interested.

Also, with the mufflers, SLP Loudmouths will be considerably louder, but I think going with a cutout will be a good idea and then if you choose to quiet it down for a bit, you just close the cutout.

 

7th gen 2.5 or 2.25?

 

I believe LS4 or SS models all have 2.5"

 

how much are ya trying to get for the cutout? does it have a remote? you can pm me if ya prefer. ty,joe