theres a member on the forum who has had a nice stainless steel exhaust system done for his 3.2 its the same as standard i believe but just s/s (catback system)
i would just go cat back and remove the centre silencers and use a Y piece to enter the backbox keeping it similar to the standard setup!
That'll be me.
You need to bear in mind one thing on the "current" picture you have: Although the pipes would seem to conjoin toward the rear of the car they don't; the two pipes still run independently through the aft-most box.
In essence that means that your pictures "current, "1" & "4" are all the same in terms of configuration; i.e. they are seperate pipes all the way back.
Don't de-cat it, keep them seperate all the way back and noise is not equal to power! A couple of people on here have heard, and driven, my car since the set below was added and it is not a loud set up; a little more "rumbly", but very subtle. A decent diameter (2.5") all the way back through some free flowing boxes will give you more oomph.
Here's a couple of pics to show you how standard you can still make it look; the rear cylindrical box you see has actually got two discrete straight-through pipes running through the length of it. I had mine done at long-life for about £400 and built onto the car. They are a continuous line all the way back from the cats and as they are guaranteed for life they'll never need to come off.

