Color, if you're asking someone else to do it for you, you're likely not going to find someone.
There have been TONS of 'sql' discussions here, several of them dealing with 'how do I load admins from <some SQL database x>'.
You'll need to search for them from the main page.
Now, SMF used to have a plugin that allowed for custom input for peoples profiles.
That was many versions ago.
Gmod(10?) had <some working SQL module> at the time.
At that same time, Megiddo had a Gmod Sandbox server, which, he used to pull from the SMF database to determine admins on the Gmod server.
He used this (now, pay attention, thde code is 5+ years old...IT WON'T WORK AS IS) code to pull the database info.
http://forums.ulyssesmod.net/index.php/topic,3241.msg9622.html#msg9622You'll need to convert/upgrade it for 1) Gmod 13, 2) some newer SQL module (too many come and go) and 3) convert it to myBB database query format and 4) find a way for myBB to store steam userids for that code to work.