A stupid question about overhead constructions

Hy Guys
I'm still waiting to get my first lights panel (737 overhead opencockpits interface)
I have a really stupid question and I really hope that people not gonna laugh on me :) Please be patient!

I will get the lights panel (this one http://www.opencockpits.com/catalog/...x.php?cPath=25 )

Well, I get it, I mount it, switches are correctly interfaced and working properly, weel done! I wanna go forward wit project and I wanna buy another piece of over head ( this one http://www.opencockpits.com/catalog/...x.php?cPath=16 )

The stupid question is...how they can be attached togheter?
I mean, do they need of an "underframe" to be attached togheter, or the simply need to be attached with screws.

I know that It seems really stupid but as I'm just starting I really don't know the way how it works.

Hope to get some helpful question.
Cheers guys and happy landing!

Yes, you'll need to buy or build a frame for all your panels to sit on. It doesn't need to be anything too special, as most of it wont be seen, but it'll need to be strong enough.