Where can I get the expanded manual for the Mustang GT amplifier? You can view and download the manual right here! Related articles How do I update the firmware on a Mustang GT or Rumble digital amplifier? How do I use the MGT-4 4-Button footswitch with the Mustang GT amps? Mustang GT Firmware Version Release Notes Where can I get a copy of the Mustang GT Quick Start Guide? Are there foreign-language translations of the Mustang GT Expanded Owner’s Manual?