Identifying a Williams PA Diesel

I am not aware of any data base of Williams locomotives.  As for the year it was manufactured, that is a tough question as well.  They were made for many years starting in the late 1980's to best of my knowledge all the way through ownership by Bachmann.  There isn't a lot of difference between the models.  Some of the earlier ones had Ott sound systems, but otherwise the parts are pretty universal.  I don't recall if the PA goes far enough back to have the motors without flywheels like the early FP45s, the SD45 and a few others. 

Not sure I was helpful, but hopefully a little?