How can I rename these to keep is organized?

I'm not really sure how I can fix this without breaking the script I have... My UI GridLayout is lining things up by name which means if I have TextButtons named Item1 - Item25 its will line up like this... https://gyazo.com/805ff1f14c19c08ed9f387dce6c7f4b3

But If I change that then it will break my script:

script.Parent.ClickDetector.MouseClick:connect(function(Player)
    local items = Player.PlayerGui.InventoryGui.Frame.Inventory.Inventory
    for i = 1, 25 do 
        local itm = items:FindFirstChild('Item' .. tostring(i)) 
        if itm.ItemNumber.Value == 0 then
            itm.ItemNumber.Value = script.Parent.ItemId.Value
            itm.Image = script.Parent.PicId.Value
            break
        end
    end
end)

Anyone have a suggestion?