Side exit/AAR style exhaust

Okay, chassis exit. I assumed that you just meant an exit in front of the rear wheels, not an exact copy of the t/a-aar exhaust.
Ive got a 3.5 system with giant flowmasters to the bumper that i really like, but you said no to the flow (lol). I made another 3.5 system with left over pipe, and hooker aeroflow for my other car. Ambivalent about the sound at first, but ended up really liking it. The aeros are also kind of a chambered muffler.
Third car is a tube chassis car with fenderwell headers that exit in front of the rear, but thats cause the mufflers run under the rocker panels.That car uses magnaflo straight-thru, but they're long 3" in/out, so fairly quiet.
The bumper length system is very heavy, so im thinking of using some 3 1/2 jones straight-thru glasspacks,to save weight if nothing else, straight off the collector. (They are very long, 30" or so, intended for diesel pickups). You could do something like that, then bend a piece of pipe to exit where you want.
Ive got 3.5 collectors, and dont use reducers if i can help it, but 3.5 mufflers are few, and expensive. My flowmasters are now 200 each, the aeros are 100, the jones im looking at are 50. The flowmasters and aeros were half that, when i bought them.