i ported the manifolds to get the most out of them. i did 2.5" from there into high flow precats to a x pipe all wrapped. from there i did 3" after the x pipe to flowmaster single chambers race mufflers. on the drivers side i went under the tc tail housing and then straight back. i had to cut the front gas tank skid plate where it mounts on the frame to get the 3" pipe through. i have swivel ball connections in two places so everything can come apart. it sounds nasty! i do have clayton long arms so routing is alittle easier. i had this done with the stock a arm and it still worked nicely. i have a dana 60 in the rear so now it is really tight back there. i had 10" of lift and im back down to 3" so it can compete with my bros srt-8 jeep at the track.
its not impossible to do but its hard but take ur time and do it right. just buy mandrel bends and weld it up. This is the youtube link to the uconn car show i did a couple years ago for kicks. this was old motor with your 218x cams. Enjoy