Adjustable shelf?

Okay so I'm upgrading to a 250w hps light system with just a reflective wing, I grow in a 2'x4' closet and always leave the door open on the closet so it's not like I box myself in and have a huge heat problem overall. I want to be able to get the 250w as close as possible obviously so I want to use fans to cool it. I do not and cannot exhaust in any way so that is not an option for keeping the light cool. My plan is to just use a fan that will blow across the light and another fan to then blow that how air out of the closet into the room. It's the winter here so I can keep the room as cold as I want so as I said overall heat is not a problem just the immediate heat being radiated off the bulb.

Any ideas on how I can keep these said fans(small 6" fans) adjusted to the same height as the light as the height on the plant grows. I was thinking of putting an e track on the two walls that would have an adjustable shelf that clipped into the e track that I would clip the fans to. I cannot find anything online of a shelf that would clip into an e track, is anyone familiar with something like this that can point me in the right direction?

Right now I have a fan blowing on the light source and I have a fan blowing into my tent. If you have a dimmable ballast, you can observe the temp. I have to keep my a/c at 70 when the lights are on to keep accurate temps. What temperature is your grow space when your lights are on?

Could you give us a few pictures of your setup? That way it will be easier to visualize things.

Thanks for the responses but I have since found a way to make it work. I bought a vertical rubbermaid fast track bar that I attached to the two walls with shelf brackets that i can easily attach to the vertical fast track every inch or so on the bar so I can start low and go high. I then just use my clip fans to clip onto the shelf brackets, so I have one fan blowing across the bulb and another on the opposing end of the bulb blowing out of the closet. Works perfect and allows me to get the bulb within 3-4 inches of the tops of colas.

Got the rubbermaid stuff from lowes:
Two of these upright rails: http://www.amazon.com/Rubbermaid-Garage-Storage-Upright-1784365/dp/B000LXA9RK/ref=sr_1_7?ie=UTF8&qid=1447006061&sr=8-7&keywords=rubbermaid+fasttrack

With two shelf brackets to clip the fans on(except mine is only like 7" not 16") http://www.amazon.com/Rubbermaid-FastTrack-Garage-Storage-Bracket/dp/B0009J5NXG/ref=pd_bxgy_201_img_2?ie=UTF8&refRID=0VY9NWTN4BWV9FS7V8N0

And two clip fans from amazon:
http://www.amazon.com/Lasko-2004W-2-Speed-6-Inch-White/dp/B00FXOFO7W/ref=sr_1_1?s=home-garden&ie=UTF8&qid=1447006166&sr=1-1&keywords=clip+fan