Unfortunately, if you want your truck to perform like it should....you are going to have to retain the catalytic converters and all 4 O2 sensors. My guess is that you are thinking that the catalytic converters are restrictive and is the reason that you are wanting to remove them. This is a common mistake. Now....on yours....since you mentioned that the exhaust is "shot"....I would guess that your catalytic converters have a few miles on them. It would be wise to go ahead and replace them....IMO rather than just leave them on there. Deleting them is not an option. Not because of emissions testing....but because your ECM needs the input from those two O2 sensors to run correctly. Without them, you will have your truck experiencing trouble getting out of its own way.
As far as the rest of the system.....you have a lot of options on mufflers. You also need to decide if you want to run true duals or not. Difference being that true duals have basically two of everything and do not have any type of crossover pipe (x pipe or h pipe).
Bottom line here is that you need to forget about deleting any of what you mentioned. If you need help deciding on what to get for the rest of it....go to you tube. There are plenty of people on there who have uploaded videos that include them showing off their "pipes".