Is there any way to piggyback my regular mobile handset voice channel to the existing hands-free setup in my '98 E? I don't mean the actual service, which has been covered here already, but just the sound.

I use a little cheapy earpiece with in-line microphone which plugs into my handset, but the car's mike and speakers have to 10x better.
Remember those old CD players that used some sort of fake cassette tape that went into the tape player? I'm thinking along those lines.

-rb

I'm sorry that I can't give you the source, but when I was doing research on installing a phone in my Mercedes, I discovered that I could buy, I think it was, a Motorola hands-free car kit that would use the Mercedes sound system (mute the radio and all, and use the car speakers, etc.). It would not, however, use the steering wheel controls. Try the audio section of this board and perhaps you can find more info.

Thanks. This gives me something to search for. I'll repost in that section.

Your best bet is to forget about the factory phone setup if you haven't already. I ordered an Audio Mute Lead
from a company in London that will interface directly with the factory radio to mute it when the phone rings as well as play the incoming voice over the front stereo speakers. This will work great for me because I also ordered the Dashmount gadget that allows for no drilling to mount the phone rather than having to akwardly having to use the armrest location. This will all work in conjunction with the wired Motorola hands free kit for my new T-720 phone.