I don't think any of my 2000S's have serial #'s. Some of my other heads have a stamped metal plate, but I don't know of any way to get info from the number. If you are trying to find out info about it, usually the date of manufacture or factory QC testing is written in grease pencil somewhere on the inside of the chassis.
There are a couple of versions of the 2000S, if you post some pictures there are several people on this forum that can give you specific info about your amp.
