How To Install Blinds On Double Hung Windows . Outside mounted blinds cover up part of the frame and the mounting bracket holes will show if the brackets are removed at. In other cases, you place the headrail into the brackets and slide covers onto the. Inside Mount Blinds Double Hung Windows Sofa Cope from sofacope.com Attach the headrail to the brackets. Open the bracket door and hold the end brackets in place. You can see the depth of the windows is not that deep and i am afraid that when we hang them.