Dean,
I was able to get out yesterday for my first run with the replacement s/s mufflers. They did relace the defective mufflers N/C, but my cost for shipping & re & re mufflers was about $540.00 can. + my labour.
I did fab & install the transition cone in the inlet side.
If you look at the posted photo by mickmate (above) you can see the difference in the upgraded version of their muffler.
I went with the 2 1/2" core as previous & I am very pleased with the sound, I can again enjoy driving without blood running from my ears.
NOTE!
I still get that fluttering sound on de-cel below 2000 rpm. & idle, but no tweeting with this set. I did a few mid throttle spurts (roads are still pretty dirty from the last snowfall) & the sound was very nice & I did not have to wince at all.
In fact it was so smooth I found myself surprised several times when I checked the tach & saw the rpm much higher than I thought.
So far so good
Regards Craig