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@juanpa102 Editing the vehicles.meta adds the ability to have multiple liveries.

To actually add multiple liveries in game, you would have to make a copy of the livery, which is named a_sign_1 and rename it to a_sign_2. To add a third livery, rename the file to a_sign_3 and a fourth livery would be renamed to a_sign_4 and so on.

Then go into the metrotrain.ytd and drop the a_sign_x file there, which would automatically convert the file into a texture. Hopefully the livery should appear in game.