Brake differences between Gen 1 and Gen 2

So got into new brakes on the 2010. Ordered the Z36 Powerstop for front and rear.
Still waiting for the fronts. But just for interests sake does anyone know the differences
In rotor sizes from these two generations? I’ve got a pic of a conversion guys are using on their 60 series land cruisers.

This is Gen 1 comparison.



This is my new Z36 Gen 2 rotor. So how much bigger are the Gen 2 over the Gen 1? Is there really a higher towing limit of Gen 2 over Gen 1? My buddy says it’s the brakes that really matter for tow limits. I don’t want to get in a technical argument over that, there is a certain amount of sense but obviously not the entire reason. Is the hub deeper on the 2nd Gen? I'm just curious here