I recently replaced my muffler (which was split from scraping too many driveway aprons) with a stock muffler. When I got it and climbed under to install it, I was surprised to find a stainless steel system down there /ubbthreads/images/graemlins/grin.gif The problem was, the stock muffler wasn't the same fit as the stainless one and I had to cut off a piece of the old muffler pipe to fit the stock muffler to the stainless tail section. The moral of this story is that not all systems are the same, and mixing one type to another may result is some creative engineering to fit it all together. Not only do you need to match the size and length, but make sure you have male to female connections on all the joints.
Even though I missed the growl of the split muffler, after time the stock muffler developed into a nice sound...took about 2 months, but I like it now.
Bruce /ubbthreads/images/graemlins/cheers.gif