Has anyone successfully (without burning their house down) built a canopy around an enclosed fixture before? I've got a great deal on a LNIB Current Orbit fixture for my 125 gallon tank ($500
http://www.current-usa.com/outerorbithqit5ho.html). I'm thinking of buying it and then building a canopy facade around it in such a way that the fan holes on the fixture are aligned with fan holes on the canopy. The top will be gapped wood with plenty of escape for heat.
The alternative is to pay $300 for a canopy kit on eBay, $1000 on retrofit lights, and hours and hours in assembly and paint.