what your talking about is called "true duals", not straight pipe.
true duals on a truck that new is going to be a bit tricky, and expensive...and illegal (meaning most exhaust shops are going to turn you down). if memory serves, you have 4 cat converters from the factory....that combined with a downstream o2 sensor for monitoring cat efficiency will make doing this without tripping a CEL tough.
also, i hope you dont have your hopes up for huge horsepower gains with this setup. it will SOUND better than single or split exhaust...but performance will be nearly identical to stock.
you will need to run an equalizer pipe (aka. an "H" or "X" pipe) in order to get the proper sound and to avoid killing your bottom end torque.
you'll have to have at least one cat converter on each pipe. you may be able to get away with locating the downstream o2 sensor in just one of the pipes...or you may try installing it in the equalizer pipe. im not sure how it will react to either situation.
if your just after the look of dual exhaust, you'd be much better off just replacing your factory muffler with a single in/dual out unit and running the 2 pipes back. im personally not a fan of split exhuast...in my opinion it just adds weight and complexity while still droning the way a single exhaust does.
