I have run Car Sound (magnaflow) ones on may different set-ups. You can typically find them in the 60 dollar range.
I have run as set of these on my Lightning for over 35K. Pass every year too
...... Pick up some power, loose some weight, save a ton.
http://cgi.ebay.com/ebaymotors/2-5-2...mZ140124365178
For your 3.o guys, You can cut the old converter flange off, bend a pipe and mount the converter a few inches down flow. You may have to extend wires on the 2 rear O2's.