DIY 400w cooltube?

So im thinkin of buyin a cooltube (actually i NEED one for my 1 plant box) and from wat i see these pre made ones can get a little pricey even without the proper fan so im wonderin is there like a way to make one of these yourself and like how do i do it so the bulb wont be leaning on the glass and everything and like wats the cheapo way of ventilating them?

Best tutorial I've bookmarked :

DIY: Best Cool Tube - Grasscity.com Forums

Good luck!

thanks man

o n if anybodys interested in this i just learned about duct boosters i think like 80-300 cfm and at most 50 BUCKS!props to mane2008 (somebody get this man some rep STAT)