Do a search here for pin removal tips. As a start, the pins have a knurled section just below the flared top that really holds them into the hinge-especially if they have been there for a while. The pins are NOT 1/4" diameter-look for proper replacements, though you might just want to use SS bolts if you're putting on side mirrors. If the pins are old, there is a good chance that they have worn a groove in the side of the pin,corresponding to a ridge on the hinge. If they are not coming out,try moving the door to several different degrees of opening. You have to find a place where the groove and ridge aren't mated to allow the pin to move, otherwise you are hammering pin against hinge-for a very long time.