This is from ebonite on drilling a predator pursuit, it is also a asymmetrical weight block ball. Good Luck and I bet it needs some polish
Ball Choice: All pin-out distances, all top weights
Reaction: Early breakpoint, strong arc backend hook style
Suitable for: Full rollers
Flare Potential: High
Pin Placement: 3 3/8" from bowler's center of span, located in an 8:00 direction from the center of span. (For more length and less flare, place pin 2 inches from the bowler's center of span
BOMB Placement: 1 5/8" from the bowler's center of span, located in a 2:00 direction from the center of span
Balance Hole: If needed, place 6" from center of span in a 2:00 direction to remove excess positive side weight, 6" from the center of span in an 8:00 direction to remove excess negative side weight