As you probably already know, "Paul Newman" daytona is now used pretty generously. It can apply to reverse panda, gold watches, non-art deco fonts, etc...
The modern ceramic 116518LN with "Paul Newman dial" is nicknamed this due to the red minute track ring around the dial.
You have to remember though, that it was the dealers who created and popularized this idea and they really only meant 1 dial at the time. The idea continued to expand beyond to reverse panda, to different bezel combos different reference numbers, different fonts. To the point now, where dealers use it however the hell they like.
It's been well documented that Paul Newman himself has at least 5 daytonas he has worn. Most of them would not be considered "Paul Newman daytonas"
1.
The original 6239 steel bezel with Paul Newman dial that sold for $17.7m.
2. The
6263 acrylic bezel with reverse panda, non exotic dial. Also given to him by his wife and engraved. He left this to one of his daughters. But this is not considered a "paul newman dial".
3. The
16520 white dial daytona. Given to Paul Newman by Rolex and worn by Paul Newman. However, this is not considered a "Paul Newman dial"
4.
The 16520 black dial daytona reverse panda. There are photos of him wearing this, but not considered a "Paul Newman dial".
5. The
116519 White gold daytona reverse panda. There are photos of him wearing this, but not considered a "Paul Newman dial".