I mounted drop-down blinds in the bedroom a while ago. I like to have the window up at nights, the only problem I have is that the drop-down blinds makes noise when they move in the wind. Therefore, I made a snap clip bracket that could hold the blinds in place. The Drop-down blind bar that is attached to snap clip bracket is oval. See picture with dimensions and see if you can use fixing brackets. drop-down blinds hanging secure when they are attached to snap clip bracket.