I have 8 coal hoppers configured to load Brick Clay with 6 Woodchip cars coupled behind them. The Woodchip cars are configured to only load woodchips BUT the first two in line load the remaining Brick Clay. Why? The Woodchip cars are from rgcx and their kuids are 2:128368:630049:3 & 2:128368:630051:2. Thoughts or suggestions?