No, these two axles will not work together in 4x4 mode. The decimal numbers 4.27 front and 3.73 rear refer to the respective gear ratios. The front axle requires 4.27 revolutions of the prop shaft to create one wheel revolution...4.27 to 1 ratio. The rear is 3.73 shaft turns to one wheel rev. Quite a big difference. The higher the decimal number is, the lower geared the axle is. With the low power output of a 152, the numerically high, but low geared 4.27 to 1 ratio was a good choice to help get the vehicle out of its own way from a dead stop, at the sacrifice of top speed. People really weren't concerned with bombing down the highway at 75-80 when the Scout 80 model was new. If you had v8 power and were planning on a mixture of pavement and offroad driving, the 3.73 ratio would be pretty ideal. It isn't really the best match for an under powered I-4 engine. It would only be worse if larger than stock tires were added. In terms of 4x4 operation, the axle ratios need to be the same front to back, or drive train damage will occur.
