Great Thread! Brings back so many memories!
The earliest car stereo I remember is a Pioneer Radio Cassette Receiver in our '86 Premier Padmini. It had a manual tuning knob at one end and a volume knob at the other end with the frequency indication in the middle.
It looked somewhat similar to this.

Somehow, this player had an issue with International Albums, the cassettes used to get stuck in it. There was one incident when we were travelling to native (240km~8 hrs drive those days) and MLTR got stuck in the player. It refused to eject, but was playing well. The same cassette played over and over through out the journey while I got an earful for playing that cassette!
Everyone at home still burst into laughter whenever that incident is mentioned.
Later when stereo players where available with high speed dubbing, I used to painstakingly record cassettes before each long journey. Used to spend hours to get an hour long play list.
Later I started burning Audio CDs, then MP3 discs in the same fashion, selecting each song. I still continue the same habits, but now with ZipDrives and neatly numbered and organized files and folders in them.
Spotify has taken over now and I cannot remember the last time I downloaded a song. Life has gotten more easier these days, but I somehow miss those days.
Going slightly off topic;
Even today, I cannot shake away that feeling that the earlier receivers added more charm to automobiles whenever I see retro fitted touch screens in today's cars, I just love the OEM ICE in earlier VWs.
Few among the modern receivers bring back that charm; the notable being Blaupunkt Bermen SQR 46. Looks are very deceptive and this unit for sure packs a punch up its sleeves according to ace tuners.
https://blaupunkt.com/cus/product/bremen-sqr-46-dab/
I have this first generation Duster which came with a non Touch Screen ICE system. I upgraded the system moderately with a 4 channel amplifier and better component speakers, but left the head unit untouched to retain the old school charm. It is almost at the end of its life cycle and I am yet to find a head unit which will blend into the environment. Physical buttons and dot matrix displays
The only worthy product is the Pioneer MVH-S622BS unless something else catches my eye.
https://www.pioneerelectronics.com/P...ers/MVH-S622BS