What counts as a major event? 40 years ago would have been 1985. So, 1985 - 2025?
The men’s association was a bit in flux, to put it nicely. CJ did win the 1996 World Championship, but it was the PCA, which was his own breakaway Association. Not everyone played in his PCA, but Earl and...
You could always buy the go/no-go gage built specifially for pool ball measurement to ensure they're in specification. But, if you were going to go that route and spend the money on the gage, you wouldn't have been looking for the cheapest balls.