I did the same, and left the cat on. Quiet when cruising, louder when you step into it. (Not terribly loud.)

 

Well here is what I did, we just pulled the muffler off and it is exactly what I want. Thanks to all for the ideas.

 

While were on the subject is that first chamber on the exhaust the cat and is it required to be left on in inspection counties?

 

Yes that's the cat. Where I live we have inspection and it will have to stay when I go through, BUT right now my vehicle is new so doesn't need to be inspected.
I think new vehicles are exemp for a few years.
THere's talk of not doingf inspections soon, we'll se.
For now though, cat will stay, I'll see how loud the Nelson is. Some say removing the cat leads to a drone I don't want.

 

I just installed a 5" striaght pipe system from citymuffler.com (they sell on Ebay). But instead of running staight I put in a 51" Donaldson.
This thing sounds GREAT!
It's just a touch louder than stock (maybe not even louder, just deeper) when cruising on the highway or around town. No droning
The truck also seems to have a noticable increase in torque. My truck always seemed to be a bit of a dog 0-60 empty even worse towing
Now with the new exhaust it seems to accelerate much quicker with less dipping into the go pedal.
I can't wait to see what it is like when I get a Smarty straped on.