Now that you have the beginning and the end of your script in front of you, realize that you have something very valuable in front of you: what your script is about.
If you've been writing for more than three days, you'll realize that this is the answer to the worst question in the world, whether it come in a studio meeting or at Thanksgiving from your aunt. What's your script about?
Divorce yourself from what you know about the script (or think you know). Look at the beginning and the end. Does it match what you thought? Ask your friends what the script's about. Are they with you on this? If you have general agreement, you're doing well. If you don't don't despair -- BRAINSTORM.
Which script actually interests you more? The one on the page or the one in your head?
Have you learned something about the script you didn't know before?
In talking to friends and the little editor in your head, did you come up with anything even better?
Keep asking the hard questions. It's NOT as easy as it sounds. Dig into your assumptions. And come up with two gifts to yourself.
A single sentence that encapsulates the script.
A single word that captures the THEME of the script.