Do you like it?
I think that true duals with two flowmaster 40 series mufflers and 3" tips would sound great.
Also, if you only remove or gut the rear cats and keep the O2 sensors in the same place you shouldn't get any check engine light. Quite a few guys on here have done it with no problems.
Nice rig I just had duals done on my 4.6 2 weeks ago. I had them hack off the muffler and run duals from just behind it all the way out the back with 3 1/2 tips. Sounds saweet and no popping or light...



