Reverse bulb number or series number

Hello, very good afternoon, I need to change the reversal bulb of my American Ranger Pickup, 4 cylinders, automatic, the problem is that not knowing the number of part and starting from the year until the year the refaction is compatible with my 1987 model, in the refactionary they take me for spare parts that are not adequate, if someone can help me I will thank you very much.