How do you change the size of a mesh when using a mesh dropper in a tycoon? [closed]

Below is the code im using but when i change size of drops it does nothing

wait(2)
workspace:WaitForChild("PartStorage")

meshDrop = true
--------------------
-- Mesh Settings: -- [If you want a mesh drop, set meshDrop to true up on top.]
-- Look at the mesh properties and change the inside of the quotes below to the appropriate
-- full link or the rbxasset:// style, doesnt matter which one you see in the mesh you want

meshID = "http://www.roblox.com/asset/?id=16190555"  
textureID = "http://www.roblox.com/asset/?id=16285875"
--------------------


deb = true 
script.Parent.Clicker.ClickDetector.MouseClick:connect(function(wat)
    if deb == true then
        deb = false
            local part = Instance.new("Part",workspace.PartStorage)
            part.BrickColor=script.Parent.Parent.Parent.DropColor.Value
            part.Material=script.Parent.Parent.Parent.MaterialValue.Value
            local cash = Instance.new("IntValue",part)
            cash.Name = "Cash"
            cash.Value = 70 -- How much the drops are worth
            part.CFrame = script.Parent.Drop.CFrame - Vector3.new(0,1.3,0)
            part.FormFactor = "Custom"
            part.Size=Vector3.new(2.5, 2.5, 2.5) -- Size of the drops
            if meshDrop == true then
            local m = Instance.new("SpecialMesh",part)
            m.MeshId = meshID
            m.TextureId = textureID
            end
            part.TopSurface = "Smooth"
            part.BottomSurface = "Smooth"
            game.Debris:AddItem(part,20) -- How long until the drops expire
            wait(.15)
            deb = true
    end
end)