Mark,
I have the converter module that enables RCA connections with the factory radio. I have an 04 Accord. it plugs into the bottom of the factory radio (where a cd changer can be added) It cost $100 but it was well worth the cost versus the FM mod. I am changing SIRIUS receivers and will be hard wiring a kenwood.
Are you interested in the module? or a XCAT reciver? not looking to "make money on them" just a fair price. I used the RCA connections from the XCAT to the modulator. worked awesome.