Kit #572513 is the Generation I kit. This is the kit I have on mine. Look at the description "K&N Fuel Injection Performance Kit *For 1997 Models- Kit will only work with FA-1641 cylindrical style air filters." I don't understand why they say it will fit the cylindrical style air filters only though. I had no problems mounting it in place of my square air-filter and air-box that came on my SOHC. If it was a Generation II kit, it would be in the description like the Chevy C/K is "5730131 K&N Generation II Fuel Injector Kit Fits C/K (old body style) only" If you notice that when you fill in the vehicle application information section for the Generation II, it comes back with a message "We're sorry, but this part is not currently available for your vehicle."