Look closely at the pictures in this Ebay ad. There are TWO pieces there that move against each other. Bolt the slotted bracket tight to the engine in the middle of its travel, set the initial timing by turning the distributor housing, tighten the pinch clamp, and let the vacuum advance move through its limited range of motion to adjust the timing for load conditions on the engine- - - -acceleration, cruise, passing, etc.

www.ebay.com/itm/266847684437?

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!