Irti

Hey guys, hoping someone can point me in the right direction. I'm trying to install the powered Kicker sub in my 2026 GMC Sierra 1500 Elevation (non-Bose) and I’m stuck on where to find the speaker harness to tap into. I’ve attached pics of the gray and black harnesses that everyone always refers to in other threads but the issue is mine only has 3 wires going into it, and from what I can tell those are definitely not speaker wires. I also noticed another module right next to those two (attached picture) with one large connector going into it. Could that be where the speaker outputs are instead? On top of that I can’t seem to unplug/unlock this harness to pull it out, I’m pretty sure it has something to do with the red plastic thing but I’m not sure where or how to pull/push it so any tips on releasing it? Appreciate any help, this new gen wiring is just throwing me off. Thanks in advance https://imgur.com/a/YV0JFpc