temporary add_to function of some sort for vehichle based around a part that combines two vehichles into one would prob be best option. Still would be some hard coding there.
Or Remote controlled vehicles & maybe even GPS guided vehicles that follows __ spaces behind and __ off axis (± tiles)
or just __ spaces behind and have it center vehichle on lead vehicles center path.
Second option sounds harder on the code though, and less flexible.
Then theres the aisle cart idea I threw out there but thats pretty code heavy as well as best as I can figure, and devs seem to agree.
Unfortunately vehichle towing has been essentially halted by most any potential “fix” requiring hard coding.