As you probably know some Land Rover gearboxes always suffered from mainshaft/input gear spline wear. This is due to the fact that oil isnt able to get the the splines to keep them lubricated and reduce wear. On later models of the LT230 transfer box rover fitted cross drilled input gears. These gears simply had holes drilled into them allowing oil to reach the splines. Also, oil feed plates were fitted to get important lube to splines. You can fit