EXCLUSIVE: Darlene Love, Judith Hill, Merry Clayton and Tata Vega are profiled in the Oscar-nominated Radius-TWC documentary and will perform at the 2014 Film Independent Spirit Awards on Saturday. It will be the only musical performance at the ceremony. Director Morgan Neville’s 20 Feet From Stardom, a look at the lives of several of the music industry’s greatest backup singers, is nominated for a Spirit Award in the Best Documentary category. It also made the cut as one of the five nominees for Best Documentary Feature at the Oscars. Currently the No. 1 documentary on iTunes, the pic continues to build momentum as the culmination of awards season approaches. Hosted by Patton Oswalt, the Spirit Awards will be handed out during a daytime luncheon in Santa Monica and broadcast later that evening at 10 PM on IFC.