Hello Brendan and Joe
The screw-in muffler is round, smaller, and more noisy.
Some manufacturers chose the optional Hush-Tone for market placement reasons.
It is a quieter, larger, and more expensive muffler.
If you have ordered a new muffler, the cheapest option is to have it re-coiled.
I understand why you would like to keep it to the original 'spec'.
Hope this helps.
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JACK
