Will again take a look. I used Google to find a tutorial and that dpole of said cog, but I wasn't able to find it.
I just made this screenshot in a chrome-based browser for you:
Top left here: https://imgur.com/xCgrot0
If you click on that, the "Server URL" field is where you want to put your private instance: https://imgur.com/Gua3jSb
There is a small cog in the top left side where you can change the URL to use when you login, in case you simply overlooked it.