I removed the radio from my car entirely. It is very difficult to get good sound in our cars. As you know, glass transmits sound well, particularly low frequency sound, which is all around when driving. And our cars have lots of glass, so even if other issues were addressed, the lovely expansive greenhouse in our cars is going to allow in a lot of ambient noise.
Then there is the fact that our cars originally had very little sound deadening and even if you add a bunch yourself, there are certain areas -inside the doors, in the fender near the rear windows, behind the dash and the roof - that are difficult to treat. Without treatment, lots of ambient noise will encroach through these sources, particularly the larger sheet metal panels (like the door skins).
Add to that the fact that it is difficult to find places to install speakers. High frequency tweaters best transmit sound close to ear level facing the listener; you would need to use the A pillar to achieve that. Low frequency drivers need a solid installation so that the energy from the movement of the woofers turns into sound waves and not vibration. etc., etc.
AM radio for listening to baseball games, sure. But if you want to listen to music, install a blue tooth speaker in the center speaker location and run it off your phone.