Cut them off underneath the plastic with some good sidecutters - if you can't get in there then cut the plastic instead - and then desolder each pin individually.
Yep - You can use an exacto or any sharp craft knife to cut off the plastic - Then you can heat the pins from the top, or longer end, and just pull them out with a pair of pliers. Clean up excess solder off the board and you could sand the solder pads with 360 Grit wet/dry. Solder in new connector pins.