looks like you successfully duplicated the euro sport muffler that was installed on my 914-6 in Germany circa 1972
(and which i am still running)
.
and - or - the old school town-and-country version
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"... I am German, and if it has no logic it's meaningless."
914 & 914-6 parts FS 03-2021 
www.tinyurl.com/2pmpmv8y
911 parts FS 2022
https://tinyurl.com/911-Parts-FS-LCM