You could always take the fan off the engine and go with an electric unit.
The amount of drag the fan creates really drags down the power. The fan alone is good for 2-3mpg. I started out with a stock motor that had been bored .030 to restore the compression. With this setup I was getting mid 9-10mpg. I then went from points to a Pertronix ignitor and re-gapped my plugs. This helped but only a minimal amount. I then pulled the stock intake and replaced it with an Edelbrock performer. Hell the valve covers were off so I went ahead and installed Comp Cams 1.52 roller tip rockers. At this point I saw no need to install the old distributor. It was replaced with an HEI unit with an MSD coil and wires. When I put the breather back on the carb I put a taller element in it so it could breathe a wee bit better. After all this I was getting a solid 12MPG. I then installed my electric fans at the same time I put on the Vintage Air and March Performance underdrive pulleys. My mileage the last time I checked it was 14.75. By the way this is real world driving in the left lane of the interstate, running the air. I don't ease around babying it just to see what kind of MPG I can get.