4472, borg warner?? you must really like the heavy stuff, the 1372 is lighter and its still a heavy pig.
From what I've researched, the 1372 and 4472 are essentially the same animal sharing most parts in common (the main difference being the output splines on the 4472 are 32 vs 27 in the 1372. The viscous coupler is also different giving different torque biases but is physically interchangeable.
It took me awhile to understand how it worked (not sure I do completely yet), but it appears that the planetaries in the 1372/4472 act much like a differential, but the torque is biased to the rear.
The viscous coupler acts much like a traction enhancing device in a differential (positraction, torsen, etc.) in that it will lock the front and back together when there is slippage between the two, but it isn't involved in the torque distribution.
There's an even heavier-duty (and likely heavier) NVG149 AWD case that is in Escalades and FS gm trucks/vans. Likely works on the same principles, but has been essentially bulletproof in large V8 applications in heavy vehicles.
The big benefit of the 1372/4472 is it supposedly bolts up to a 4x4 T5 (even though it never came that way from the factory). The front axle on AWD s-10/t-10/Astros where the 1372/4472 was used is essentially the same as the 4wd axle, but without the ability to disengage as it is not necessary on an AWD drivetrain (and would damage the viscous coupler if allowed).
If you wanted an AWD box that bolts up to a manual transmission and is going to handle a moderate amount of power in a relatively light vehicle, then the 1372/4472 with a T5 is probably the simplest and cheapest way to go about it - the parts are in salvage yards all over the U.S. and are common enough that they can be rebuilt with standard parts from multiple vendors. The T5 and the 4472 both have their shortcomings in heavy vehicles or high-power vehicles with sticky tires because they "see" more loads that way.
Cool as it would be, and I'm new to the Locost world, I don't know how easily it would work in that platform, mostly due to packaging constraints. You can "clock" the case off the back of the trans (within reason), but there's not a lot of room to go down in the locost and going up just makes packaging worse.
If you were building a "street" locost, it might be worth raising the seats up or raising the whole chassis height, and AWD is a nice thing to have on wet streets and the extra ground clearance would be practical,. Are there a lot of locosters driving regularly in the rain? Anyone driving in the snow?