I want to know the answer to the following question:
Who placed the Sakya viceregal regime position of authority?
All the background I'm provided with is that "In 1358, the Sakya viceregal regime installed by the Mongols in Tibet was overthrown in a rebellion by the Phagmodru myriarch Tai Situ Changchub Gyaltsen (1302–1364).". Is that enough to answer the question?
Answer: yes