I’m hooking up 2 ds18 subs to one amp and 2 other amps for the highs (8 6x9 ) speakers)If your just hooking up a sub (you only need one connection) then use the stock sub wires
If there isn’t a dedicated box in the trunk then there should be a sub mounted in the middle of the back deck lid
Multi meter will give you polarity
If it was me I would disconnect it but you can just splice into it if you want to keep the stock sub in play
As new as that vehicle is, there should be no reason WHY you couldnt contact a Chevrolet dealership or contact GM and get a diagram.??I have a 2022 Cadillac with a factory Bose amp. I am in need of a wiring diagram to connect a hi lo convertor to the speaker wires