The modern stereo system

FYI, I just recently found that some companies make a Bluetooth amp.
No actual stereo needed at all, and it has sub output.
Any Bluetooth device can connect to it and play your music.
It also lets you use your phone for navigation info over the stereo.
I use mostly Bluetooth in my car for music, navigation and hands free phone calls.
May be an option.

There are a bunch on Amazon pretty cheap. There are also ones that are targeted to old vehicle use like what we have, but they are 5-10 times the price. Don’t know what you get for that, probably just a lot of markup.