We were having issues with my wife's 1971 440 Six Pack Challenger running a little warm only on super hot humid days driving for extended periods of time in slow moving stop and go city traffic.

The car has a 26" radiator and I wanted to keep the factory belt driven cooling fan. There was limited space in the front of the radiator with a transmission cooler mounted there too.

I wanted a fan that wouldn't overload the car's factory electrical system.
I ended up using this 14" Maradyne curved blade fan.
https://www.summitracing.com/oh/parts/mar-m142k/overview/

I mounted it offset on the radiator using the correct relay wiring setup and a toggle switch.
You will need some type of support bracket to use with the nylon push retainers for mounting the fan.
The fan I used had multiple slots to mount supports.
I used a bolt mounted vertically in one of the bottom slots and ran it through the bottom of the radiator support then using a nut and a jamb nut on the bolt securing the fan in place.

We don't need to use the electric fan much but it's nice to know it's there and the fan does a great job of cooling the car down when it's needed.