Conversation so far:
What was Vidal's first screenplay?
In 1958, the director William Wyler required a script doctor to rewrite the screenplay for Ben-Hur (1959).
How did Vidal become involved in Ben-Hur?
Vidal rewrote portions of the script to resolve ambiguities of character motivation.
Was his work on Ben-Hur successful for him?
In exchange for rewriting the Ben-Hur screenplay, on location in Italy, Vidal negotiated the early termination (at the two-year mark) of his four-year contract with MGM.

Question: Where did he go after that?
Self-contained rewrite: Where did Gore Vidal go after that early termination of his four-year contract with MGM?