If you’re buying a brake kit you’ll need to know what hubs your car has. You can’t guess since these cars are old and might have the hubs changed in the past. 240z and 280z hubs are interchangeable. 280z hubs are thicker and stronger than 240z hubs. Most 260z came with 280z hubs and suspensions.
To check what Front hub you have take off your front wheel and look at the hub. Round shape is 280z and “X” shaped is 240z hub.