As a 92 400E owner, I am looking for new wider tires for my car.
Does anyone know how to do this?
Can it be done by a DYS, or does it need to go to the shop?

Stein

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This webpage does a good job of explaining the process.

its not too difficult to do the job as long as you have the proper equipment.

the key is not to rush it, take your time, and make sure you heat the fender a little so it has better flex and to prevent the paint from cracking...

ic... so ... what do people do with the plastic liners that are present in wheel wells on some cars?