ok thats a very akward space without pics i dunno, the RULE is...5000-7500 lumens per sq. ft of ground....every bulb that you go to buy will tell you how many lumens it puts out, i have a DIY clonebox that is 18" wide, 14"long and like 23" high and i am going to put 2 of the 125W CFL (act. wattage) at 8500 lumens each in there, but like i said, HPS 50-75 watts per sq ft. MH for veg 25-50watts per sq. ft and cfl go with about 7000lumens per sq ft. like i said i am posting pics tommorow if you msg me i will send u link and that will probably really help you out bro im serious it is almost the same size as ur shit and i am going to do what you plan on doing. like i said, ^ i am going with a 400W HPS for flowering in a 3x3x3' area, and a clonebox/vegbox that is 2'x18"x2' tall with 250W CFL 6400K (act wattage) just msg me and ill hit u first thing in the morning like 11am central time and we can actually figure this shit out ill help ya bro just msg me ill get back to ya in the morning