Ron, without a gear change most back yard mechanics can do an locker install since you just need to set the black lash and blue dykem the gears to make sure the teeth engagement pattern.
But if your thinking of changing gear ratio...the D44 in most jeeps is a 15lbs turn torque on the pinion gear after a .06 shimming on the back bearing face after you reach 0.000 face thrust. Your Center line to pinion face cant be off more than .005 or the gears will fail within 12,000 miles. I think the Dim is 3.750 for axle C/L to pinion face +/- grind C/L written on the pinion gear.