Slice the root/stem ends off of the zucchini. Slice it in half & hollow out the middle with a spoon, leaving a zucchini 'boat' with about 1/4" flesh behind. Season the inside of the zucchini with salt, pepper, & garlic powder. Mince up the zucchini 'insides' & add to a bowl. To that same bowl, add the rest of the ingredients & combine. Scoop the crab filling into the zucchini boats. Bake on a baking sheet or in a casserole dish for 40 minutes, uncovered.