Piston's hairline cracks

Hi

I'm rebuilding a Navigator lump and have found some fine hairline cracks between the gudgeon pin holes and the bottom of the oil scraper ring slots

Advice  please anyone??

Obviously I'm tempted to replace but do I need to ?

I'm sure the lightweight Guru's will help but for my money any cracks in any piston isn't good news, if they are available easily then I'd change them.

Of course most of the NOC tech wizards have the opposite problem, cracks in the hairline!!  

Cracks in pistons!!! Put them back in and on your head be it!! In fact you will probably be on the other end when the engine blows and you fall off! The Navi and the Electra for that matter seem to do this as a matter of course.

By the way what's rondelli doing on here? When did he have a 'little bike' Mind we don't pull some of your hair out the next time we get hold of you. Lov Al