A really simple but very useful mod that gives you access to every car chassis and piece in the builder at any given time (even ones you can't normally use): In GAME DATA/OBJECTS/BRICKS, there's a file called UNIQUEBRICKS.TXT, which contains "All the bricks that can go in the game ever". Now, see UNIQUEBRICKSGENERIC.TXT? It lists "The generic bricks - available in all worlds". Simply overwrite it with a copy of UNIQUEBRICKS.TXT, and boom, every chassis and piece is acces