Which Antec case do you have?
If it's one of the 600-series or 800-series, begin by removing the side panel, then unclip the upper section of the bezel using the obvious latches visible at the edges. Now you can see a couple of retainers sticking out the top of the lower section of the bezel. Gently pry them outward while pulling the lower section of bezel straight up. edit: or was it straight down... I haven't done this for a while, but now that I think about it, I think you do pull down for removal, not up.
If you have one of the 1000-series cases, take off both side panels and you can see the clips that are holding the bezel to the case. There are three on each side. Gently unclip the bezel and pull it off.