Do you have the harmonic balancer and timing cover removed? If so, I guess it would be possible to get the gears out of time. Otherwise, there's no way to drop the crank far enough to disengage the teeth. That seems like a lot of unnecessary work just to change a rear seal, however!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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