are you wanting to use the mirrored doors as the sliding barn doors? or take them out and install the wood type sliding barn doors?
https://www.youtube.com/results?search_query=DIY+add+wood+frame+to+mirrored+doors make it solid so you can add hardware for sliders https://www.youtube.com/results?search_query=DIY+turn+mirrored+closet+doors+into+barn+sliders
Keep in mind that a barn door needs a wall without and electric switches and hvac vents to block it from sliding.
Yes the wall surrounding the doors is clear of electrical, etc.
Yes, that is my primary concern. I've been toying with two ideas but don't know if either will work.
A. Attaching the wood necessary to anchor the brackets to the back of the mirror doors using a super strong adhesive.
B. Building a shallow rectangular wooden box that would slide over the vertical ends of the mirror. The brackets would be attached to the back of the wooden box. This would also make my plan to trim thes doors to look like French doors.
Done ... simple advice would have been appreciated.