Scrog Grow

So i have a dresser that is 56"H, 35"W, and 18"deep. I decided that i would do a scrog grow and try to fit about 7 plants. For the screen height i figure i will go about 12-16" above the soil which would leave me 44"-40"inches left to work with. Then take away about 12" for the light going in and i am left with 32"-28" of flowering room. The dimensions all work out perfectly, i am just wondering what light i should use. Idk if a 400watt HPS is to much, or if i should lower the wattage. This is my main problem that i have to solve. I will figure out ventilation after the lights. Any help would be fantastic. Pics will be loaded once the project gets rollin.

A 400W(maybe even 250 too) light will get too hot, in my opinion. You would definitely have to rig a dedicated exhaust system with some ducting and an inline fan, plus you need to duct the heat somewhere. You may be better off going with CFL's. It might be better to only grow 4 plants and let them veg longer. I can see 7 plants getting awfully cramped in there, SCROG or not. Just my two cents, though. Other people might disagree.