How can I tell which version Dual Caliber - DC Series amp I have?

Determining an original DC from a later DC Series Amplifier:

Original DC amplifiers have a two position toggle switch on the front panel that provides manual switching from Rhythm to Lead.  These models also feature a five position rotary switch on the rear panel for manual EQ selection.  Later model DC's have a three positon toggle switch on the front panel which is labeled(top down): Rhythm - Lead - Lead/EQ.  These models feature a two positon toggle switch on the rear panel for EQ channel assignment.