Grumpy Cat
Elio Addict
It actually depends on where you live:Rather than running it through the radio, get a low cost set of walkie-talkies and a mono headset with a mic (you can't legally wear headphones when you drive).
Yes, I know someone will pop in and say that they use two earbuds all the time, but if you got pulled over with them in, it's a ticket.
Having both ears covered (or filled) makes it difficult; if not down right impossible to be able to hear warning sounds when you drive.
http://drivinglaws.aaa.com/tag/headsets/