GOOD GROW CAB IDEA? check it out!

hey everyone! im gonna be doing my first grow here real soon, and i think i have researched enough that i feel ready. I plan on starting with autos, just so that i can get a feel for the marijuana plant. My goal for growing is to have a couple OZ's or so a month of personal smoke and to sell around a HALF POUND every month.

I plan on growing:
- Low Life Auto-AK47 (main cash crop, highest yielding auto)
- Short Stuff Onyx (sounds dank and i want it :])

I am going to build two 3'x3'x4' boxes. they will be lined with mylar. I'm going to stack them ontop of eachother so that it turns into a 3'x3'x8' cut in half. This will be great for me because i can have monthly perpetual harvests with autos, thats all i need to do is add the exact same stuff on the top box once i get the hang of things!

Equipment:
- 400W HPS w/ Easy Cool 6 hood
- 200CFM in-line fan
- 2 50CFM PC fans for circulation
- FFOF soil

Here is my grow box plans for ventilation, lights, etc.
does this look good? I want to grow 9 plants in each box (1 plant per sq. foot)



does this ventilation setup look ok? PLEASE give suggestions comments feedback ANYTHING!!@ im really high and growing weed is all i can think about i am so excited for my first grow alright peace! thanks!

I would turn the cab on its side and have your exhaust pulling through the 2 reflectors with a filter on either end (more beneficial if on the intake side of the reflectors). My dimensions are a little different, but same concept. You didn't mention what lights you would be using for the top box so I assume it will be another 400?