They don't, and they're, well, I won't say trash, but they're not that good. What I did was I finally got my original AM/FM restored (approx $700.00), but I also installed a Custom Autosound hidden radio under the back seat. it comes with a wireless remote so it's undetectable. It's not a cheap system, but it does sound good. Unlike the original AM/FM mono!
You can read about it
HERE, but I don't know if the Custom Autosound SRMS radio I got is still available or not. The link on ebay doesn't show the pictures anymore, but
HERE'S A LINK to it on Amazon (currently unavailable).
I'm sure there are other "hidden radio" options, so it's something you might want to think about.
Ed