I have a Single blade e fan out of a Buick century that i used in my firebird with a 350 and stock radiator with a 195 stat, it never seen higher than 200 degrees on a hot july day.

Do you think it would be sufficant to cool a stock 5.3

 

The problem might be when you load the truck down or tow with it. Only one way to find out.

 

And if you do tow/haul the next question would be what radiator do you have?