I don't know what my muffler guy used to trim my factory cut-outs on the SSE, but it was done nicely so the tips would fit level.
It'* possible to have the guy doing your work cut the valance panel back there to make room for the tips.
I used a MagnaFlow with ANSA dual resonator tips. The tips were a bit too big and he had to customize them a little. One more trip to the exhast shop and I'll be done.
A couple of things need to be 'adjusted'.
If you don't want too much noise or a farty sound with an aftermarket muffler, have a resonator put in.
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