To knock out pins that are peened over you use a punch that has a head size of the dimple depression in the centre of the pin. When you tap it with a hammer the peened edges fold up to allow the pin to be knocked out. When replacing push the pin back in the way it came out and use a punch the full diameter of the pin to peen back the edge of the pin. You will need to support the other side of the pin on another flat punch. Better with two people doing this (use the domestic help). Can also be squashed back in a vice if you are careful with some packing pieces or even small ball bearings.
Baz
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