I was thinking the OEMs were 740, but I could be wrong. More CCA's is not a bad thing.
Today, I finished the mod where my FRS radio, when someone else transmits, will mute the AM/FM/CD and then the FRS audio plays over the car's speakers. Also, I have independent volume control, no matter what the AM/FM/CD is set to, when it mutes, the FRS radio's volume control determines the level of radio traffic over the car's system.
Also, when I transmit on the FRS, it also mutes the AM/FM/CD. No more scrambling for volume controls when someone says something, or I want to say something, on the radio!
(I have the NAV head and it has a "telephone mute/takeover" feature in it. Took me a bit of messing around to get the interface right, but I am very happy with how it works. I'm using a Kenwood TK880 radio.)
One more step to being ready for the Dragon...