iPad to C203, how?

I am thinking of adding an iPad for SatNav and music server. How do I connect the iPad to the Merc's existing audio system?
I think the most basic would be thru the cassette player, but sound sucks and not being USB, it wouldn't charge the iPad. Any better way to connect them?
Thanks for helping.
<<Sorry for double post as I also posted it under C203 forum. Not sure how to cancel that one as I think this is the right forum to ask.>>



