Well, you could, but the -242 is a full time 4WD case. It does have a 2wd selection, which is probably what you're looking for. Either the -231 or 242 will bolt in place of the -247. EDIT: The 231 is a part time case, 2HI/4HI/4L The 242 is a full time case, 2HI/4HI(full time)/4HI/4L
You need to make sure you match the spline count on your transmission when you get the new T-case, or get a new input shaft for the T-case.