Look on the outside of the distributor housing. Some models have a round, slotted nut that requires a special tool to loosen/tighten it. A field-expedient tool can be made by grinding a slot in the blade of a flat-tip screwdriver.
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!