Does anyone know if the lettered and unlettered forneys come with the same detail parts? Separately packaged and otherwise?

Thanks guys, now I just need to determine which variation is best for the kitbash. Do the Forneys come with alternative headlights?

Are there enough individual parts available from bachmann to kitbash a 0-4-4T forney from the parts available online is do is my only option to buy an entire 2-4-4T and remove the from wheel set? What are the detail differences between the different froneys?