It's not uncommon to get a stiff-turning shaft when the rope seal is first installed. It will loosen up somewhat as it runs. As long as the starter will spin the engine without excessive current draw, you're probably OK. Given these old engines' tendency to leak, a slightly tight new seal is probably a good thing!
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
Love your enemies and drive 'em nuts!