All of the SCSocialWidget modules have a surrounding class like:
sourcecoast facebook pageplugin sc_facebookpageplugin
You can use that to target a specific module type. Also, you can use the Module Class Suffix option to add your own module class to that specific module and add whatever CSS you want for it.
I hope that helps explain. Either way, I'd recommend looking at the output HTML to find a style you want to target to add the appropriate margin as necessary.
Thanks,
Alex