This is the only reference I could find
المصدر : مصباح المتهجد – الطوسي ( ر ) – ص 752 – 758
However this sermon was not delivered on the day itself when the prophet appointed him but it was delivered after the prophet had passed away and it coincided that the day of Ghadeer and Juma happened on the same day so the imam after his Friday speech he spoke about Ghadeer