the antec p180 is a great case to start off with. i love mine.
i used some swiftech components to watercool mine, and although it took a bit of modification here and there, i'm pretty happy with the way it turned out.
here's a pic: https://webspace.utexas.edu/dgs287/IMGP1599.JPG?uniq=-mq73kq
i would say that both of the fans you had in the top left portion of the case need to be exhaust. they're high and in the back, meaning the heat has risen and that air has probably already been 'pulled' across the case. use the front fan that comes with the case as the inlet. and, if you can manage, don't remove the upper HDD cage, and place another fan on it.