I've seen an out of place box (about the size of a deck of playing cards or so) inside the DS rear fender well. This is probably what you're talking about. On the 450, you can remove the plastic cover panel for the jack, and get to it pretty easily.
Rookie
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The phone transceiver is much bigger than a deck of playing cards. The two connectors that plug into the transceiver are probably about the size of a card deck when they are plugged together.
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Looks like this?
http://forum.ih8mud.com/showthread.php?t=66185