We installed a solo boost modification in this amp, with separate boost levels for each channel. We used a transistor based switching system with LED indication on the front panel.
We replaced the mono channel switching footswitch jack with a stereo jack, and tied the solo boost circuit to the jack "ring", so the solo boosts/channel switching could be actuated with any standard Marshall 2-button footswitch, even those with LEDs (which do light up to indicate lead channel and/or solo boost).
