Amen on the fronts, James. Just like tires, I don't wait on them to wear out.
Dave, it took all of 5 minutes. On the bottom of the brake back plate, under the axle, is a 1/4"x1" slot. They may have dust covers, mine didn't. Look inside and there is a small star wheel. Look to one side or the other and you can see some threads. This is the turnbuckle that spreads the shoes out.
I didn't put them back together last time, but mine were such that I spun the star wheel downward (with a screwdriver blade). I could see from the threads that it was pushing the shoes, so kept going until I couldn't easily spin it. I think I went too far, so will play with them some today.
It was SO easy that I could kick myself for not crawling in the snow and mud to do it before. Also, does your E brake work? Mine didn't, which was the giveaway for brake adjustment. I had already checked vacuum.
Phil