Try running the following code in the command bar in Studio.
for _, id in pairs(game:GetService("AssetService"):GetAssetIdsForPackage(243881675)) do
local model = game:GetService("InsertService"):LoadAsset(id).Parent
model.Name = tostring(id)
model.Parent = game.Workspace
end
You should see that in the inserted models there are two folders, one containing the R15 body parts and the other containing the R6 body parts.