Uh let’s kill that one. I have mentioned this lots before but it is confusing. Your Stemme does *not* need to be on the STC AML. Your A&P should not be using this STC as basis for a major modification. They sould only using this as justification for the pairing of the TT22 and TN70. Your installer should refer to FAA AFS-360-2017-1, INSTALLATION OF ADS-B OUT EQUIPMENT. And do just what is required there, and no more. https://www.faa.gov/nextgen/equipads...r(9-25-17).pdf

Please have your A&P/avionics shop talk to me if they have questions about this.

Darryl