IYAAYAS, unless you have a body shop cut out the rusted areas and weld in new metal the rust will continue to grow, and you will be chasing it forever. For that reason I would be reluctant to start restoring your 1995 E320 if you plan to do it inexpensively. Recommend buying another 1995 E320 in pristine condition, instead of throwing good money after bad on your current car. Likely a less expensive approach in the long run.

I own two 1995 E320's and enjoy the ride and build quality ... plan to keep both as long as possible, without breaking the bank doing so as I am a DIY'er. There comes a point that it doesn't make financial sense to keep a car, especially one with rust issues.

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Fred Hoelzle