Well if it is only 2wd, about the only thing you can do is drive carefully. RWD is definitely the least desirable for winter driving. Best thing you can do is lightly press the brakes and brake early. If you lock up the tires, it is going to want to swing the back end just due to the physics of there being more braking power in front than in back... Get a good set of M+S rated tires if you don't have them already.
As far as it trying to spin on ice, don't accelerate while cornering, try and let the truck coast. The inertia of the vehicle pushing to the outside of the turn causes RWD to lose traction pretty easily. Best thing you can do is only accelerate when going in straight lines, and to also do so lightly.