Improving snow traction

I got a 2 wheel drive short bed truck manual with an open rear differential as my daily driver/farm truck. I have been nursing it through the snow that we have had this year and would like to improve the traction abilities. I have a set of chains in it for when things get real bad, but they are impractical at times when I only have to cross a half of a mile of bad roads to get to the cleared roads. I have been thinking about getting a set of studded tires for only winter use for the back. Also someone suggested that I get a "lunchbox" or drop in style locker. How safe would one of those be in the snow for my situation?