i have the 4.0l in my 93 and i used a 2.25" inlet and outlet on a 17"long glasspack sounds nice if you run without a cat. does that help, also put an exhaust tip on and use a big tip it will crackle nicely if thats what your looking for
I found that just cutting the exhaust right off just behind the cat and putting a down tube on it gives you amazing sound. Did it in my 92' 3.0 L and its actually not as noisy as you would think and way cheaper.
to be honest with you it doesnt matter they make connectors to the size that is desired for your truck. So it really doesnt matter what size muffler u get. But if you are one of those people that has to have everything perfect than 2.25 should do it.