4.11's will make 5th. gear pretty much redundant. I'd suggest a 4.56 or 4.88 if it's available for a good compromise between load pulling and top gear cruise RPM in 5th. A 4.11 with the OD and tire height you've got would put 5th. gear cruising speed somewhere in the 80 MPH range. That would be white-knuckle speed for me!
Jerry

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