But if Buford Tannen comes looking for trouble, I'm gonna be ready for him.

4 seconds sound clip from the Back to the Future Part III movie soundboard.

You can hear this line at 01:08:18.311 in the DVD version of the movie.

Quote context

[...]

- My coffin?

- Well, the odds are running two to one against you. Might as well be prepared.

- So it may not be my name that's supposed to end up on this tombstone. It may be yours.

- Great Scott!

- I know. This is heavy.

- Marty, why are you wearing that gun? You're not considering going up against Tannen tomorrow?

- Doc, tomorrow morning I'm going back to the future with you.

- But if Buford Tannen comes looking for trouble, I'm gonna be ready for him.

- You heard what that son of a bitch called me last night.

- Marty, you can't go losing your judgment every time someone calls you a name. That's exactly what causes you to get into that accident in the future.

- What? What about my future?

- I can't tell you. It might make things worse.

- Wait a minute. Doc, what is wrong with my future?

[...]