Tip 1: See picture. Some people use solder suckers to remove solder. I usually use solder wick. Solder wick is braided copper. I always open up the braid. It seems to allow more solder to be wicked up and also use less. Copper is expensive these days. Hold the tip of the wick between fingers in one hand. Grab the wick a couple of inches up. Push your hands together to open up the braid.
Tip 2: See picture. I apologize for the poor quality of this picture. fNow it seems counter intuitive but it seems to help to apply some fresh solder to the joint before wicking it. I don’t know why this is but it seems to wick better. It might be the added rosin core.
USE: These tips helped me remove this connector with thick pins. See picture.
TIP: I soldered some copper wire to a couple of the pins so that I can insert it into a breadboard.