i drove my 53 3100 from 1980 to 1989 with the odometer gas gauge method.I also used the 200 mile formula. Seems to me the tape measure down the fill tube was about 10 miles to the inch. Now I'm starting frame off restoration and I have Dakota gauges in the box. Going to miss the old days I think. Also used the under dash tach for speedometer. I still have the old gauges, think I'll keep them.

Old enough to know better, too young to resist.