I am trying to figure out the year of my Marshall DSL 401. The serial number is 2000-20-1988-B. Does this mean it is a 2000 or a 1988? Or does anyone know where I can find this info?

there were no DSL's in 1988. no jcm900 or 2000's either. therefore, it means either 2000 or the aerial is something else.
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