AFAIK the ARB, Shortbus, etc. are designed so that the winch mounts "feet" forward (i.e. toward the fairlead).
I may be wrong but it sure looks like the Powerplant is designed to mount "feet" down. No way you could mount it "feet" forward on an 80 without taking out the grill, AT cooler, and probably the radiator .
Now, if you could fab up a mount so you can install that sucker feet down into the Shorbus bumper you could probably get it to fit . Probably block a heck of a lot of airflow to the radiator though.
EDIT: Christo corrected me on the Shortbus mounting orientation
It looks like a 9500i with compressor on top. 9500i can be fit with some grinding on the grill. Don't know how tall that is but did a little digging and found out that it is about 14" (+/-) tall. Apparently it is shorter than the Warn 8274. Yep, wee bit tall for the shortbus. Following link has some more info.