It's always good to start with a flat flywheel if it shows much wear. On the mercedes though planing the fw without shimming it will get your friction point low down by the floor.

The shimming might not be needed with the annular slaves, not sure.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.