I got a 870 Express witha 7 shot tube for my upcoming birthday (i.e.- I asked my wife if I could buy it and she didn't say no, but she did say this was for my birthday, Christmas, Anniversary, etc), and I can't figure out how to get the nut off the thing for disassembly.  I've read the directions, which state to slide the forend about halfway back and twist the nut off, and all I managed to do with a pair of pliers is mar the finish on the nut.

Just use a rag over the nut , or go to sears and get a wrench with the rubber strap, they will work good .

Then just hand tighten !!!

Or use an old belt or piece of scrap leather that is about the same thickness and wrap it around the nut first then use your pliars. Don't bother with cloth...no good.