[Lazy Jake]

These are just my thoughts: You, even with the engine Mods and a good tail wind, only have about 40 horsepower up front. A stock engine has a hard time pulling a car with overdrive. They will tend to bog, lug down and, possibly run hot. I would tend to run stock gears in the transmission and a good mid-range (3.56:1) rear gear. I do have a Mitchell overdrive unit in my 150B and it very rarely gets used. Finally, I avoid the interstate like the plague. Don't need an 18 wheeler turning my matchbox in to toothpicks.