[KMPrenger]

You may want to try just adding the headers first before doing the resonator delete, as they will add volume and more growl to you already mostly open exhaust. I'd if you like what you currently have, you will really like it with the shorty headers added on. (they generally add a slightly lower tone and more burble or growl as I put it)

At that point, if you still feel like you need more "loud", then do away with the resonators.