Is it possible to grant admin permissions via plugins through userPermissions->saveUserPermissions? I'd like to add admin privileges to a user I'm creating like so: 

  if($user == null)
  {
    $firstName = $_GET['firstName'];

    $lastName = $_GET['lastName'];
    $userName = $firstName . $lastName;
    $user = new UserModel();

    $user-&gt;username   = $userName;
    $user-&gt;email      = $email;
    $user-&gt;firstName  = $firstName;
    $user-&gt;lastName   = $lastName;

    craft()-&gt;users-&gt;saveUser($user);

    $permissions = [HOW DO I SET ADMIN PERMS?]
    craft()-&gt;userPermissions-&gt;saveUserPermissions($user['id'], $permissions)

}
This should do the trick...

$user-&gt;admin = true;


That data is part of the UserModel, so be sure to add it before the saveUser call.

Being a full-blown admin not technically part of setting permissions. If the user is an admin, that supersedes all other permissions settings.