I tried to have the GM CAI installed today at the dealer, but apparently it can not be installed on 21’s after it leaves the factory. On the paperwork it says “vehicle not equipped with correct RPO’s, programming not supported by GM.” The dealer had ordered the CAI and I guess didn’t realized it until they called GM. It is part of the performance package installed at the factory. Here is more information about it. https://gm-techlink.com/?p=14771. I was trying to go GM route to keep warranty intact if something ever did happen. BTW 2021 Trailboss 6.2L.