I here some people putting on straight through mufflers instead of a whole system, I have found a few but they are strait mufflers, and the stock muffler is a high, low enter and exit, how are you putting these straight mufflers on. Do you need to get angles pieces of pipe to make these fit???

Here's a handy "paste-in" that I've saved for this recurring discussion:

http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=3;t=005556

http://forum.thedieselpage.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=004826#000000

I bought mine on the internet from www.henschelandsons.com (http://www.henschelandsons.com/) in Connellsville,PA. The muffler was the Magnaflow 14771 - $149.42, the adapters were 15441 - $22.33 each. I bought 4" band clamps from a local International truck parts supplier. The job wasn't so tough, I did it in my driveway without even jacking the truck. I cut the stock muffler outlet pipe as close to the muffler as possible with a chain cutter. This allowed me to get the muffler and inlet pipe out, as well as the tailpipe. I then cut off the stock inlet as close to the muffler as possible. This left "stubs" of stock pipe inside the factory hangers. A trial fit of the muffler and clamps indicated that the adapter/muffler combo was a bit too long for the gap vacated by the stock muffler, so I trimmed about 1" off the Magnaflow inlet and outlet and the same off the 3-1/2" sections of the adapters. The stubs were also oval due to both of them being in bends in the factory install. I rounded them back out for a better fit to the adapters with a 3-1/2" pipe expander tool. I then clamped the adapters to the Magnaflow and fit the three pieces back up under the truck. When I got it where I wanted it - in the factory hangers and the tip of the tailpipe supported on a floor jack, I tack welded the 3-1/2" end of the adapters to the stock pipes. Then I released the band clamps, brought out the three pieces, full welded the adapters to the pipes and put everything back. Whole job took about 4 hours.