How is is placed on the pool table rail? with the long side parallel to the top of the rail, or at an angle?
In the beautiful picture below, rather A or B?
I can find plenty of section diagrams of rails with K66 bumpers, but none for L77.
You can see an example of this in the following video series: https://www.youtube.com/watch?v=IEmCmWUNxnw