Sorry if it seems a silly question. I took down a tv support from a bedroom wall before decorating it. It's only now I'm ready to put it back that I've noticed 2 screws are longer than the other 2. I've reasoned that the longer 2 must be the bottom ones as that would take more strain, but thought I'd take some advice first. It would be awful if I got it wrong & the support, along with the tv & a lump of the wall came crashing to the ground.