If you don't want to enlarge the rough opening, you'll need to find the largest door that will fit in the opening you have. You look at the size requirements of the door and the space you have. Sometimes the R.O. is large enough to make the transition from slider to bifold or hinged. Most times not.I am replacing my old closet doors, sliders, with bifold. The old doors appear to have had a prefinished setup. I have removed the doors and am down to studs, how do I finish this opening to install new bifold doors?