simple question.

USA Spec PA11-GM is listed for 2005 GP. Will it work onmy 04 w /monsoon as well? i have the cd/aux button, same looking reciever as one i seen in 05.

i am assuming it will, but want to check before buying. called the dealer help line on the manual, all they said was they didint know. it might work, but they never tested it....what help.

thanks,
B