There are bound to be some +/- dimensional tolerances, both on distributor housing OD and the ID of the distributor hole in the block. Since the distributor isn't locked down rigid in relation to the block, some wobble is bound to be present when the tolerances max out. Unless there's a dwell variation caused by internal play in the distributor, it's annoying, but not critical.
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!
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