Remove Freezer Back Panel?

I have Whirpool ET18NKXDN00 with the freezer on top. We have had some water leaking from up above, into the center of the fridge down below. I believe that the drain might be clogged because there is no water in the pan, under the fridge. There is ice under the trace that you can remove. I cannot figure out how to get the back freezer panel off to see what it looks like. There’s 2 screws that i have already removed and there’s a center piece that runs from the bottom of the panel to the top, which is attached to the panel. When I try to pull the panel out, it feels like something is preventing it from coming out. On either side of the center piece, there are 2 “things” that are 4 or 5 inches in height but do not appear to be removable. Any help would be great. Pic of freezer panel attached.
Thanks
DSC03907.jpg (27.3 KB)

This should help
http://appliancejunk.com/forums/index.php?action=downloads;sa=view;down=217

Thanks for the link…I have seen this diagram before, but I still cannot get the air tower out of there. Is it possible that ice is making it stick underneath?

I guess it could be possible.