Linking boats

I know this has been discussed in the past but I can not seem to find a direct answer. I have a clarion HU that has in IPOD plug. I would prefer to have a splitter (IPOD plug) come off of the IPOD and go into my boat then Y off to go to another boat so I can control the IPOD from the stereo controls at the back of the boat. Is this possible? Others have told me to use the ear phone jack off of the IPOD and split it that way, but then I can not control the IPOD at the back of the boat through the stereo remote control.

Maybe I need to have the IPOD plug go into my boat and an AUX plug go to other boats? We are linking two, maybe three boats at most. It seems that when I have the IPOD plugged into the IPOD cable for my HU, there is not enough room to plug and extra AUX wire to go to other boats (where the ear phone jack plug is). I am using a IPOD Nano (not the newest real small one).

Maybe, does my HU have an AUX Out that could link to other boats? Boat is about an hour away in storage so I can't walk into the garage to check it.