I have 13 DH wood windows that needs replacing, and am thinking about going the DIY route. After inspecting my existing windows, I found that the inside stop is behind another piece of wood (I don't know the correct name for that, maybe an "inside frame"?). I attached a couple of pictures here for illustration, one is a regular window, and the other is a window in my unfinished basement. My thinking is that it is going to be a lot of work to remove the trim, this "inside frame", then the inside stop, for an inside install. Your thoughts and suggestions are greatly appreciated!