Here is another picture,
Maybe it will give you a better idea of what I described.
Do you put the zucchini that you take out into your meatloaf (or throw it away)LOL! Tell us how much zucchini you would mix into your meat mixture???
I take one large zucchini - (at least 8 - 10 inches long), cut it in half lengthwise, spoon out the seeds, and then stuff it with my meatloaf mixture - then bake. It is delicious, covered with marinara, and then mozerella cheese. when you slice it, you have a half moon shaped zucchini slice, with meatloaf, and cheese. Pour some of the extra sauce over it.
I suppose you could use smaller ones for individual servings, too!