Hi. Does anyone know if Lowe's or HD sell windows already mulled together or if I would have to do it myself? I have never seen them. I have a side by side window configuration right now like this ( WLW ) where L stands for a piece of lumber between them that is part of the whole window unit. I want to by a unit as one whole piece to fit into the rough opening versus buying 2 separate windows and myself mulling them with a 2 x something between them. Any ideas? Thanks. Eric