buy a deck with bluetooth and done. most new pioneers come with a wired microphone - you just hook up at attach to the visor. call comes in - music automatically mutes and you either it accept / deny button on the remote and well thats it.
you hear the person thru the car speakers an you talk an drive.
my $0.02 buy the 9600BHS - wont be disappointed - at all
http://www.pioneerelectronics.com/PUSA/ ... H-X9600BHS