They're just slightly press fitted in, ya should be able to just pull them out with decent pliers......Might slide a bit of wood under the jaws and in-between the block/journal surface to pry against. Putting them back, ya just tap them in with a like piece of hardwood dowel or go easy and careful with a tapered brass punch.
Those pins is very hard steel, that took some force to mushroom them, hmmmm.....Beings they're mushroomed, they might be a bit more stubborn then normal coming out I reckon.......