I just wait until late and truck it down to the car wash,dose it with oven cleaner and pressure wash it clean.they don't even call the cops anymore.
As long as you have a driveline yoke in the tailshaft housing and go kind of easy around anyplace a shaft goes into or out of the gearbox,it'll be okay.You can even wax it so it won't grow any more rust for a while.
Speed