The modern stereo system

@Princess Valiant you would probably like the simplicity of the system I have in Gladys. I have two 6.5" Kenwood coax speakers in the doors and this sub behind the seat.

Blaupunkt THb 210A Compact powered subwoofer 120-watt amp with an 8" sub at Crutchfield

The sub does overpower the door speakers, but I have a Kicker amp I am going to put on the front speakers. It sounds really good for what it is now though.