Is a channel and/or header needed and does it provide more support for the stationary glass? We have approximately a 59" opening and plan on having a 28" door with the height around 72". We have been told two different things about a channel and a header, one says we should have both or at least a channel on the sides and bottom, the other person tells us the brackets alone will provide all the support we need. We don't want any regrets, help. We are wanting something easy to clean/maintain and of course don't want our shower falling to the ground.