Remove the wrist pin (remember the precaution about not twisting the rod) and clamp the piston in vise with a snug, but not overly tight grip. Use a thick piece of cardboard or some soft vise jaws to avoid scarring the piston. If it's an actual crack, it should open up as the piston skirt flexes a little.

Good luck!
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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