Clutch fan installation question

Honestly being able to remove the radiator to get the fit better and use studs is best.
I personally have used bolts and flat washers and lock washers because if the locks split at the oval hole… they don’t do their job. Also, small side tip- buy all the hardware from the same manufacture. Don’t miss match hardware. Spinning weight is a real cause of vibration and wear out your water pump / clutch over time. Good luck!