By gad, sir - you're a genius! Chris Amon, one of the unluckiest men in top level motorsport, in terms of the manure that surrounded him time after time. That said, I believe him to be hale and hearty in his 60s, which many contemporaries never reached for the usual tragic reason. I assume you'd read the Eoin Young (also a Kiwi, I think?) biography?
This was, for the benefit of anyone still awake, 1967, and Chris was sharing a Ferrari 330P4 with Nino Vaccarella. The retirement was before 11 p.m. I found the story in the new book "Ferrari au Mans 1961-67" by Francois Hurel, which follows on from the same author's series on Ford, Porsche & Matra (at least). Natch it's in French, but the pics are superb, and technical details are international in their nature. The interjections with little tales like this one make it a very good read if you have even basic French, like wot I have got. I bought it during the 24 hrs, and I think the (English-speaking) seller said they were going really fast. But then a Ferrari book would!
Eoin is indeed a Kiwi. I have a glass of lunch with him at least once a week. Chris. Amon is still hale and hearty, has retired from farming and is living a relaxing life on the northern shores of Lake Taupo, enjoying his boat "Can-am"