I actually used a different technique to figure out the conversion on my '46 1/2 ton with 3.55 ring and pinion and 16 x 7.00 tires. I marked an exact 50 mile run using my car that has an accurate speedometer/odometer. Ran the truck on the same route and noted the mileage recorded. Did the math and got a converter made (many years ago) based on that info. Worked just fine and is accurate.
