The tape converter is the way to go --- Sony has a good one.

But, as you already noted, the door has to be closed, and the door can
not be closed with the thick wire from the tape converter sticking
through it.

The rather thick wire can be opened up, and inside are four thin
wires.

What I did was carefully pull back the insulation of the big wire  for
the inch of area going through the door.  The four thin wires, once
separated, don't take up muck space.

Bingo, the door closes, and everything works.

Later, to ensure some durability, I put a piece of electrical tape on
the four wires.

I like the icelink,  although it will REPLACE the changer...

http://icelink.densionusa.com/

It allows the existing head to control the ipod as though it were the
changer, and works with MANY different head units.

This provides much better audio quality then any of the FM or tape
converter types...

Marty

PS let us know what you decide...