I have heard that if you align the ears on the front and back you will be fine. With bad rubber on the center bearing any misbalance no matter how slight will set up a lot of shaking.

Align the ears and replace center bearing and you probably will be fine.

Tom W

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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.