I have bi-fold beveled mirror glass door for closet, seems heavy, what I want is actually plastic glide which slides in the top and bottom track to run the pivot pin in the track. The pivot pin holder is mounted on the door frame, where pivot pin slides in has the part no. 17-4405, about 18-19 yrs. old. I need the plastic guides, your part number is 23-120. Also, how do I install the guides in the track? Is there a YouTube video?