Light mount with minimum clearance behind tank?

[gkr]

So I just moved a Red Sea Reefer 250 to my new residence. I was in such a rush I forgot to mount my Hydra52 to the back edge before pushing it up to the wall. Now its impossible to get it on with the room I have. So I'm contemplating draining all the water, do what I need to do then refill quickly, or buy a different set up (I'm not entirely happy with the Hydra anyway).

Any thoughts, or recommendations on lighting mounts or different lights that require minimal space behind the tank? I have about 2" to work with.

 

[don_chuwish]

Here's what I did for my Prime HD, I just removed the tank mount bracket and screwed it directly into the wall: