How's the openings on the fan ports? Does the sheetmetal only have small holes in it or are the openings have big enough holes so that air can pass through easily? If the openings only have small holes you might want to consider cutting out the opening and using a chrome fan grill to keep small fingers out.
Which way are your fans blowing? Front intake, rear exhaust?
Are all your wires and cables neatly tucked out of the air flow paths?
Cricket