I have a good idea and some advice for you. Of course, I don't know how well it will work, but here goes..
1st.. use the entire chest of drawers. Get your hps up near the top where the top drawer would go. Normally, people use a movable (by chain) light, but in this model, you will move the plants by shelving.
2nd.. you will need a wood shelf and a glass shelf cut to the inside measurements of the cabinet. The glass will be difficult, as you will need it as flush as possible to the wood on the sides. This glass will need to be fastened just below the light to protect the rest of your grow setup.
3rd.. Use a hole saw to drill out big holes in the sides of the chest.. maybe 3-4 per side. Radio shack has big, high flow AC "Muffin Fans" made of metal (I use the smaller version of these for my veg. computer case, btw.) which you will need to attach as intake on one side and exhaust on the other. You will need to cover these somehow with something lightproof to maintain your stealth. You could possibly shield them w/ black rock wool or such (and carbon-filter on exhaust) between the fans and the light and then put a loose black foam or such on the outside. The only tricky thing about them is the noise. There will be a definite fan noise when lights are on, but this will probably move your air. The more fans wired in parallell safely, the better.
4th.. Use the other wood shelf I mentioned in the beginning like a bookshelf.. move it up and down with the plants, as needed.
5th.. Coat EVERYTHING inside with aluminum sheet bonded with something fire retardant. Foam, maybe? This will protect your cabinet from catching fire, thus saving your life. Then, use flat white paint for your reflective on top of the aluminum. I know it's not the BEST reflectivity, but it is decent and its heat disspation properties are what you're after here. You can make up what you lose in reflectivity with some ghetto co2 (sugar-water and yeast).
6th.. grow away, but continue to fear and I'd not leave the house with that thing on, to be honest. HPS / MH are hot as hell.
DISCLAIMER: I take no responsibility for anything you are about to do. You simply asked for ideas and I am providing one. Now, for the advice..
Personally, I think the best idea presented on here was to keep the cabinet and your stealth, sell the HPS and get yourself 2 sets of SERIOUSLY kickass CFL's - 6500's for veg. and 2500's for flower. You can even use screw-in ac adapters like I do in my grow.. makes it UNREAL easy and cheap to set up. In the end, you will save an ASSLOAD of money (1 time AND monthly.. 600W for 12 hours per day is SERIOUS buck on electricity bills, man) and keep your own personal safety, as well as the safety of those around you. Seriously.. going stealth means you are free to do whatever and can take away some of that fear. You bought a light big enough to make a small grow ROOM - not a cabinet. Probably spent a bunch, too. Re-Ebay that bitch and get to work the way MANY people are doing it on here. Seriously.. there are guys on here growing CFL that put some of the MH / HPS guys to shame nowadays. Serious.. peep this:
https://www.rollitup.org/indoor-growing/141891-my-stealth-closet-grow-must.html
This guy's getting ready to harvest soon and he did it by re-vegging in something a lot smaller than what you've got. Imagine what you could do by growing your seedlings, topping a couple times, lst'ing during veg and then a SCROG? You could get an assload of sweet, sweet cheeba out of that cab, man. WITH CFL's! There's an entire forum under Indoor Growing about them. It's really the way to go. On top of that, "the man" won't even register a cfl grow. With more and more cities adopting smart grid technologies, they will be able to see EXACTLY who is growing with MH / HPS. As soon as that 600 W spike hits every 12 hours, you'll be a sitting duck for the handcuffs. I know.. I helped implement smart grid technology for a while. CFL's, conversely, use such little power that you could grow PLENTY using 200W or less in an apartment and no electric company would need to be the wiser.
Dead serious, man.. ditch the HPS. I know it's completely uber and all that, but ask yourself a simple question: Would you rather have weed and do it safely or risk your life and gamble burning your crops with a "cool grower's light" anyways?
Peace and luck, man.
try putting a tray with ice in it and put that in front of a fan. and just point the fan upwards blowing cool air to the light. It's pretty simple, wont really cost you anything, and i think it would work pretty well in a closet.(I'm Still a big noob though). Also get something to exaust the hot air out , just leave the door open every now and then. tel me how it goes bro
