Update: I was unfortunately not aware of Shamus Young's severe criticism of Fallout 3 available here to link in the original piece and I regret that. It dovetails rather nicely with what I've written and it's much better executed than my piece. I strongly recommend anyone...
Learn what the different Globlins do and you're in with a better chance.
Look for big chains at the start to fill up your tank.
Remember to read what the characters tell you to make sure you know what you're trying to do.