I'm about to put the drill to work and ventilate the beast, is it worth it? Whats the best pattern to use for the holes?
If you haven't already done this, the HRC-recommended cutout looks like this.
I used a scroll saw to do mine- worked really well, but make sure you use a blade suitable for plastic (finer teeth) & don't go too fast or the plastic starts to melt & get gooey.
I have a .pdf of HRC's dimensions somewhere (it's online, too, but I can't remember where) so let me know if you want it & I'll dig through my files later.