Google Ngram puts it even earlier: https://books.google.com/ngrams/graph?content=rocket+surgery&year_start=1900&year_end=2000&corpus=15&smoothing=3&share=&direc

Google Ngram puts it even earlier: https://books.google.com/ngrams/graph?content=rocket+surgery&year_start=1900&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Crocket%20surgery%3B%2Cc0 https://books.google.com/ngrams/graph?content=rocket+surgery... And I started using it at least before then. It's too obvious to not show up quickly.