installation of basketball rim

Put up a basketball backboard and rim on the 4x4 trellis beams on top of our driveway - in an structurally sensible and aesthetically pleasing way. The backboard - I'm thinking - would be about 4 ft wide x 3 ft high. Sort of like this: [login to view URL] We could buy the backboard, but I want to make sure it gets installed in a way that lasts and looks good. The beams are about 8 ft off the concrete - so the bottom of this backboard should roughly be the beam level. (Sort of like in the third picture attached.) Which means we'll want to construct a rectangular piece that goes ABOVE the beam, and supports the backboard. And this rectangle itself may need to be supported by diagonal pieces going from top of it and diagonally down to the beam. I can't trust myself to do a good job, but I can help.