My first thought after reading your request was - forget it - look for a modern device class.
I do not know anything about car radio players, but I have some questions about the display ...
- is it a static display of two independent lines of 8 characters each?
- is it a dynamic treadmill display, with two independent lines?
- is it a dynamic treadmill display, which maybe uses both lines together folded as one line?
- how does the car radio player display the full information like Artist, Title, Tracknumber etc. from the ID3v1 tag?
- does there happen any truncation of ID3v1 tag-field's content while displaying?
- does the car radio player complain when the media file contains two tag-types of ID3v2.3 and ID3v1?
- does the car radio player display just the media file's name or some tag-field content from the ID3v1 tag or both?
Read also ...
Even Latest Version Does Not Delete ID3v1 Tags
DD.20140306.0927.CET
DD.20140306.0954.CET