Exaust for 2001 4.3 LT Blazer

I tried the search button but came up short.  I'm looking to get a new muffler.  Looking at Flowmaster because it was the first one I came across.  Most like the sound.  Does anyone know what size and type I need?  Is it just a bolt on or do I have to cut?
 
Any help would be greatly appreciated.

You will definitely be cutting and adding pieces unless you get a cat-back kit.  I got a center in, center out 2.5" in 2.5" out Flowmaster super 40....That's the only muffler made IMHO