Hi Karen,
don't care. I'm living on the sunny side of the globe and so is my mood.
However, if the LM386 is too weak you might try an LM380 with 2.5W output power. Considering the low power necessary to listen to the radio (about 250 to 500mW) that output should do, even if your engine sounds like hammer and nails. (like all Izusu cars).
There are two versions of the LM380: 8 pin DIP and 14 pin DIP. I suggest to use the latter type. It has six extra GND pins for better cooling. Plan for at least 4 square inches of cooling surface on the solder side.
If you are in need of a circuit PCB just give me a note. I've made one with any available space as cooling pad. To increase cooling you might add an IC-heatsink.
Kind regards
Hans