The clod is the cut at the shoulder. Similar to a pork shoulder. The fore rib is the first four ribs roughly where the neck connects so it gets a lot of movement. Unlike the ribs that are further back and do not move much, these are not as tender. But they will be just as good, and should have a very buttery texture. Typically though would not have the amount of intramuscular fat since it is more of a working muscle.
One of the things you may want to consider is once you impart the smoke in the first hour or two, is to use a crutch or a Dutch oven and finish it with a braise.