I think on you antenna most people wouldn't replace the cable all the way to the antenna because it has a fitting on it at the antenna that most shops don't carry. You should find that there is a standard male female motorola connection at the rt sight side.

As far as the 89 124 I would reccomend an alpine 6 cd changer in the right side panel( it actually fits behind it) and an alpine mp3 cd in dash. As far as speakers as I always do I suggest the rainbows for the dash as they snap in easily and sound great and for the rear I use a 4 in eclipse in the stock location. There are other possibilities depending on how big of a second you want to take out on your house...... just kidding!

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The Mercedes Specialists Since 1986