The only way the pins will dislodge from the connector is if you have a tiny elf go at with a Dremel or a set of hydraulic forceps to pull it out, since the hooks/wings on the side of each pin is somewhat explosive proof, I know because I sleeve my own cables and removing one pin with the best of my might without a pin remover left me gasping for air. There's also the matter about the latch on the connector, pretty much all connectors won't come loose unless they've been abused.
Now, to the point, what is the make and model of your PSU and how old is it, if it's being reused? What connector are you referring to?