I would say we need at least 5 piles of items. Each carousel looks to need at least 12 items from each pile. More if they will be the porcupine models. One pile will contribute 24, top and bottom rails between posts. all imo
edit: assuming 6 across x 9 or 10 high when finished, I would say 4 or 5 carousels. Hope that doesn't ruin the ending of the show for some.