I've wanted to do that all my life.
2 seconds sound clip from the Back to the Future Part III movie soundboard.
You can hear this line at 01:33:24.149 in the DVD version of the movie.
Quote context
[...]
- Reach!
- Stop the train just before you hit the switch track up ahead.
(STEAM TRAIN BRAKES SCREECHING) (2)
- Uncouple the cars from the tender!
(STEAM TRAIN WHISTLE BLOWING) (2)
- I've wanted to do that all my life.
- What are these things, anyway?
- Marty, are the time circuits on?
- Input the destination time. October 27, 1985, 11:00 a.m.
- Check.
[...]