There is a little retainer washer on the pins - I first used a thin screwdriver to get underneath it and started prying at it. I then used a hammer to move it out so the retainer is up against the bracket again then pryed some more until the retainer slipped off. I think you could use a c-clamp and socket as a press though. Put the socket on the side that does not have the removable retainer and tighten. The hinge pin should slide into the socket until the retainer slides off the other end.
Sent from my "two hands on a keyboard"