I wanted to post this here in case anyone wanted to get some ideas on their own ride. I couldn't find anything anywhere about someone doing something similar to their '18 or '19 Traverse before I started this project and it definitely would have helped me. This was all done in a 2018 Premier.
So I installed a pair of Stereo Integrity 6.5" and Audiofrog 2.5" in the doors. I created a custom mount out of 1/2" and 3/4" MDF for the speakers, and the 2.5" speaker has a small enclosure of ~0.2L. A substantial amount of CLD tiles was stuck to inner door panel, outer door metal, and inner door metal. The holes in the doors were covered in sheet metal, a layer of closed cell foam and them mass loaded vinyl went in there too right behind the interior door panel.
I fabricated mounts out of ABS for the 1" Audiofrog tweeters, which went in the stock locations at top of dash.
Mount for circuit breaker made out of 1/4" ABS.
I used a PAC AP4-GM61 to get a clean audio signal from the factory head unit. I created a mount for it out of 1/8" ABS and secured it underneath the passenger footwell. This unit also has a non-fading level control knob that I installed in the center console.
The amp rack and enclosure for a JL Audio 10TW3 I built to fit into the removable cargo bin area. I routed all the speaker and remote connections through a MOLEX connector for easy connect/ disconnect in case I need to get to the spare tire. The DSP is the Alpine PXE-0850S and the amp is Alpine PDX-V9. The control for the DSP just sits in my center armrest storage area.
Thanks for checking it out!