We ran into a problem: The supposed 2-1/2-inch exhaust system, wasn’t. After further measuring, the pipes leading into the mufflers were 2-1/2-inch, the mufflers were 2-1/2-inch, but the pipes traversing over the rear axle were 2-1/4-inch. Doh! To remedy this problem with our current 2-1/2 inlet/outlet Flowmasters, we applied a bit of creativity. We knew that trying to compress the Flowmaster’s 2-1/2-inch outlet to the 2-1/4-inch tailpipes wouldn’t work, so we used a hacksaw to cut slats on two sides of the new muffler’s outlets. Later, as the muffler clamps are tightened, the muffler’s outlet should compress onto the smaller pipe without major leaks--hopefully!