How to combine to channels under different emails?

[Heart Family]

Hello. I am trying to combine my two channels and keep the views/subscribers. I have watched a number of videos on how to do this, but am having trouble making my main channel show up as a brand account on my 2nd channel. My main channel is tied to a gmail and 2nd is under yahoo email. I added the 2nd account as a manager through Google+ thinking that would link the two, but it still will not show under brand accounts.

Anyone have any ideas on what I need to do?

Thanks for the help!