Any side play in the upper bushing will allow the point gap to change, which alters the dwell and the timing. There should not be any noticeable side play at the area of the cam that operates the points. Roll the engine around until the points are fully open, then move the shaft around and watch the point gap change. Then go get yourself another distributor!
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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