Small block mileage

Some years back, the Wifey and I took a '70 Dodge truck on a 2k mile trip. I had a 340 in it with a TQ, MP cam, headers, 2.02 J heads, backed by a 727. I put 2.76's in the back and got 16-17 mpg on the trip. In a truck @ 65 mph (that was the speed limit then). I lowered the metering rods on the TQ, boy could a guy get MPG with a TQ