67 318 running temps in the summer
Does the fan not fit on the engine side? As a pusher it will be less efficient since it’s also partially blocking the incoming air. Which may be why you’re running hotter on the freeway when you should have more air coming through the radiator.
How are you switching the fan? Or are you just running it all the time?
Do you know your pulley diameters or the pulley ratio on the water pump?
Done properly they’re more efficient, free up horsepower and can provide more than enough airflow.
That said, lots of people don’t set them up properly.