[Msquared]

So...I did install the Audiofrog GS25 in the dash and their GS690 woofers in the doors of my 1LE. No other changes so far, and it's a huge improvement. I mean massive. It has more extended highs and lows with much more detail but also no harshness. Vocals are leagues better, bass is much better in both extension and quality, ambiance is much improved too. I went with these speakers mainly because of their high sensitivity combined with good reputation for sound quality. The G25 have tabs that make these drop-in replacements, which is nice. I don't really use the rear speakers at all: I just fade them out. My last phase of the plan is to install a Kicker KEY180.4 amp and use it in biamp mode to actively cross over the door and dash units. It has an 35-band auto-EQ that should improve staging and frequency response, too.

AFAIK, there is not yet any interface for our non-amplified systems (e.g. NAV-TV withich is available for Bose-equipped 2019+ Camaros). So I don't think there's any way to attenuate amplified chimes and warnings, even with DSP. I think the only option right now is to use speaker level inputs and carefully consider how much sensitivity to dial into an amp.

ETA: speaking of hating to cut factory wires, I am using a "breakout harness" that Gen5DIY made for me to go between the factory harness and the tuner module by the glove box. It will allow me to put the amp in the circuit for the front speakers without cutting any factory wires. I will still have to run a separate set of leads between the dash speakers and the amp to avoid cutting those, but that will mean zero cuts in factory wires.

Also, I didn't know about LLJ Customs dash speaker adapters when I did mine, so I made my own using the stock speaker's connectors and hi-pass capacitors. You should plan to use some kind of high-pass filter for the dash speakers. If I knew about them, I would have bought the LLJ adapters and added a 200uF cap in the positive leads (corresponds to the recommended crossover point for the GS25 speakers).