There are limitations, but the guys at the source have the most comprehensive Prius add-ons available. They have been doing this since the Prius first came to America. If they don't have a way to do it I doubt anybody does. As for GPS, I have heard of one person who added it (to a first generation, I think) and it was pretty hairy. The nav system doesn't really get high marks from owners, either. I have a Garmin Nuvi and am thinking about making a housing to fit it into the MFD glare shield when I use GPS.
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