Didn't ignore it, just missed it. Below is what I found.
"Before his death, Duke wanted a simple epitaph carved on his headstone, "Feo, Fuerte y Formal". Translated it means "He was Ugly, Strong, and had Dignity". Sadly, his wishes were never carried out. Dukes grave, in Pacific View Memorial Park, still remains unmarked to this day."
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"Addendum
After 20 years John Wayne's burial site now has a headstone. The headstone is a bronze plaque featuring an image of John Wayne astride a horse, near the Alamo.
Its inscription reads:
"Tommorow is the most important thing in life. Comes into us at midnight very clean. It's perfect when it arrives and it puts itself in our hands. It hopes we've learnt something from yesterday."
http://users.orac.net.au/~mhumphry/wayne.html