"A soft flexible coupling is used on the transmission side to cushion acceleration and deceleration shock loads and a standard flexible coupling is used on the rear axle."

This is from the book for the Model 201.

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Same thing my mechanic said when I asked why the front and rear are different.

I'd put the correct front disc in front, then just put the rear disc on the rear. Hopefully the rear disc is bad enough to justify this...

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