If you're referring to your V6, it's got enough torque to handle a higher gear but gas mileage will suffer. I'd suggest something in the 3.55 or 3.36 ratio range. I had a 3.73 gear in my 59 Burb, a mixmaster setup of a GMC Dana 60 housing, Ford gears, and a Dodge pinion flange. If you've got the 3/4 ton Eaton rear axle, the 4.11 will be the tallest gear that's available.
Jerry

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