Hey thanks for all the responses! Sorry I haven't been around here much lately....mainly because this site is pretty slow. Been reading up on ICMag and rollitup lately.

I ended up building my box using large-sized Sterilite cabinet which the dimensions I had previously mentioned belonged to. I got a pyrex bake-a-round on ebay for my cooltube which i ended up cracking from my first attempt at rigging everything up. I tried to use hose clamps and tightened them down too much so I got another one off ebay and did it better the 2nd time around. Like you guys said, 1" of air flow definitely can create a vaccuum in my cabinet. The fan I got was a Solar & Palau TD 100x which can do 100cfm or 135cfm depending on how you wire it up.

I'm on my 2nd/3rd grow now. First one was a single lowryder 2 in some sterilite tubs which turned out pretty nice. Right now I've got a single NLxshiva that vegged for over 2 months and is now in it's 5th week of flower. I tied it down a lot so its only about 3ft tall right now. I messed up on the PH and unfortunately almost ALL the leaves have dried up and fallen off. The leaves still left are slowing going light yellow. However, its been that way for about 3 weeks now and the buds still look like they're making good progress. Not great, but I'm still expecting a decent yield.

Then I've got 5 clones from that plant that are around 2.5ft tall (no tying down yet) that I just put into flower last week.

I'll get some pics of my cabinet up so you guys can check it out. I'm pretty damn happy with the way it turned out.