The Rainbows are supposed to be exact size replacements for the dash speakers, using the same type of snap in mounting as the old factory speakers. Since you already have door speakers up front, and don't want to install a sub, my thinking is to email or call the pros at la jolla audio about the euro connections on the rainbows, the wiring and speaker recommendation for the doors, and how to wire in or omit the fader and rear speakers. They should know about any wiring tricks with the doors. Your Sony probably puts out at least as much power as the stock unit - it is the wiring, fader, and factory amps where you are going to need some care and good advice.

As far as the sound from the front speakers, I haven't done my w124 yet except to pull the front speakers, disconnect the rear ones, and install some 20 year old full range 4.5" Concord (Harmon Kardon group) speakers made for a Chevy S10 in place of the factory speakers, still run off the Becker head unit. This was a real major sound improvement, so I imagine any 2 way coax modern speaker will sound even better, especially with a modern Sony head unit.

You might also try doing this in stages - replace the dash speakers with new ones and see how you like the sound improvement. Then worry about the doors, etc. If you want to do all the speakers at once, and are on a budget and can't find a thread discussing your exact year and model, your best bet is to contact the people that do this for a living and have them talk to you. I got my speakers for my C230 from LaJolla audio by mail (after I heard them in person), and they answered a lot of install questions for me both in advance and after the purchase.

__________________
John

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