If you plan to bake these shrimp kabobs in the oven, you may not need to soak the skewers as they will not have direct access to a heat source. Can you marinate the shrimp for longer than 2 hours?
Thread one shrimp and one scallop onto small, sturdy skewers about 9cm (3½in) long - the shrimp should be pierced through the top and again near the tail, so they're curled into a "C" shape.