Are you trying to keep the hood open? Can't you hide the pendent behind a hood or psuedo-hood (i.e., an open top box that sits on top of the aquarium that you can use to hide the less esthetic elements of a tank behind..)?
I'm not trying to nag, but I think you're selling yourself short by going to a vertical mount. It's a bit of a spotlight effect, and bulbs (we tend to use in this hobby) tend to have a better colouration in the horizontal position. And horizontal tends to have a lower profile.
Just my $0.02 .....
