XF 2.0 How can I make the old admin account a Super Administrator

I'm using 2.0.2.

I imported from vbulletin 3.8

Before I started that, userid 1 was board_admin, which is Super Administrator.

After import, the old admin account (userid 2) is an Admin, but not a Super Admin. I'd like to make them Super Admin

I tried editing src/config.php to add this line:

$config['superAdmins'] = '1, 2';

but no joy. I've tried with and without the space between , and 2.

Any clues?
That was the XF1 approach to defining super admins.

In XF2, you just go into Groups & permissions > Administrators and after selecting the desired administrator click the option to make it a super admin.
Thank you Chris! Don't know how I missed that in the panel, and every search I did kept turning up the XF1 solution