There's a world of wisdom in bygblok's comments. Especially the part about slowing down and checking everything twice. There's only one thing that I would add: Never "assume" anything!! Parts are sometimes mispackaged, machine shops sometimes make mistakes, and even published specs are sometimes wrong. If you're not sure after you've double checked everything, ask questions. What's that old saying? Can't think of the old saying so I'll make one up. "Better to ask questions and be thought to be a novice than to barge ahead without asking and prove it."