I'm planing to build mi control panel this way
(the slope and measures are exagerated)

That is, the back panel is "outside" the laterals and the bottom & front are "inside". The top "override" the size of the panel in all directions, if you know what i mean.
What could it be the best way to attach a hinge at the back so i can lift the cover?
I cant put it on the edge of the back panel because of the "descending" slope of the cover. And cant put it verticaly because in that way the cover will only reach the "horizontal" position and cant go any higher.
I hope i manage to explain my problem with my kinda ~english~
Thanks