I would like to install ARB lockers in my 78 CJ5. The jeep has 258 straight 6,354 diff, T-18 trans, Dana 20 case and 33" tires. I tow the jeep most of the time however, I drive a short distance on the highway from Pollock Pines to Ice House Road at 45-50 mph. Do you have any suggestions on ring and pinion? Should I put in 410, 456 or 488's? What would be my rpm at these gear ratio's?