The size is @5" and it is an odd size. I do a lot of 124 cars and I have found a speaker from a german manufacture that I sell that is not only great sounding but it also snaps in just like the stock speakers do and it has the factory speaker connector so it just plugs into the stock harness. It might be a 15 min. job max. Let me know if your interested they run $120.00 a pair and they are two way coaxial.

Scott@La Jolla Audio

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The Mercedes Specialists Since 1986