I wasn't able to find the exact quote unfortunately, but in the book "How China's Leaders Think: The Inside Story of China's Reform and What This Means for the Future" by Robert Lawrence Kuhn, he references the exchange.

Here's a link to the ebook preview of it: https://books.google.com/books?id=BOf_WWTKZpMC&pg=PA378&lpg=PA378&dq=clinton+76+years+mao+taiwan&source=bl&ots=376cpJiTdG&sig=U262RWdFdLNqGJWqRxdahE71YVk&hl=en&sa=X&ved=0ahUKEwiTnofM097KAhVJWj4KHV2EA8kQ6AEIITAC#v=onepage&q=clinton%2076%20years%20mao%20taiwan&f=false

Sorry about the super long link -- I'd reduce it if I wasn't on mobile.

This is not for school writing or anything. I have a minor in history and read extensively. I remember the quote was along these lines but have had no luck finding it using google. I am writing a paper in my spare time about the issue and it would be very good to have this quote. I would love to share the paper if anyone is interested after I completed it.

Thanks in advance.