Connectors Under Dash

I need to rework some connections. Can anyone provide pics and directions to remove the inserts in the factory connector I can do some rewiring work? I hate splicing stuff. Right now I just need to rework the brake light connections. One wire goes up under the dash who knows where and the other goes to the arness that connects below the steering column. I want to do some work with that harness and connector. The internal connections are square. Do they come out and how do I get them to release from the body of the harness connector?