Who was involved in delivering Sai Baba's portrait to Dixit Kaka, and where did this event take place?

The delivery of the portrait to Dixit Kaka was not done by specific men bringing it to him, but rather it was a convergence of events at Kakasaheb Mirikar's house. As explained in Chapter 51, the portrait was already at Mirikar's house in Nagar because Balasaheb Mirikar had brought it from Shirdi for repairs. After a plan was made for Dixit and Madhavrao Deshpande to travel together, Balasaheb Mirikar unveiled the covered portrait. He then entrusted the sacred picture to Madhavrao, instructing him to take it to Shirdi. Therefore, it was Balasaheb Mirikar who revealed the portrait and Madhavrao Deshpande who, along with Dixit, took possession of it for the journey.