There is no authentic source on Bhagat Kabeerji, on his life or sayings, except Guru Granth Sahib ji. About Guru Nanak, he never died. While foolish sikhs were fighting over his remains, the true Sikhs were in hazoori of Guru Nanak at Khadur Sahib. Same situation exists today. If you want to see Guru Nanak go and pay a visit to Guru Granth Sahib. Whether you are able to see him or not depends upon your piyaar and vishwas and Gurujiskirpa ofcourse!