OK then....the SD's have a different muffler system than the YD's then. Sounds like the Y after the muffler is the same as a 3/4 ton work mule. The 6.2 sounds very good unmodified. If you spend enough time searching online, you could pretty easily find a take off 6.2 system. Many a folk (and Dealer for that matter) have swapped out their 6.2 exhaust for something else.

waygfast86w, you better have pics....LOL