Just went through this saga... Towing about 7k behind the truck and a pipe (pre muffler) busted... Motor is a SBC, but pipes are the same! Wasn't able to stay off the gas, loud as ****!!!!
Bought the Dynomax system via mail order, but definitely won't recommend as it didn't fit very well! Was supposed to fit 1/2 thru 1 ton, 4wd. but.... Rt side tailpipe interfered with the brake valve and shock. Ended up buying a rt tailpipe through our FLAPs and getting it close. Neither side fit well, had to use our tubing bender to make sonme adjustments