From the NOR:
"United States Prescriptions. . .shall apply"

North American F-18 Class Prescriptions:

For use only in North America events when specifically listed in both the Notice of Race and the Sailing Instructions.

GPS Enabled Devices
Electronic devices that provide timing, heading, and heading memory are permitted. Devices that calculate VMG without the use of waypoint data are permitted. Devices that display real-time position or mapping are prohibited.

Synthetic Trapeze and Bow Sprit Bridles
Bow sprit bridles material: textile material with a minimum diameter of 3mm is allowed
Trapezes cable wires: can be cable and/or textile with a minimum diameter of 2.5mm for trapeze.

Mast Height
The upper mast height point value (8980 mm) in F.3.2 class rules is deleted. The maximum mast length remains 9100 mm from the beam

Maximum Batten Pocket Widths – Rule G.3.5
Batten Pocket width limitations for both main and jib sails are deleted

Miscellaneous
STEERING COMPASS (C.5.1.a.2) is not mandatory.