with the swicthing jack i show on the schem/layout, you can use the amp as a combo by removing the plug and reconnecting the speakers. no dummy plug needed.
as for the mid control, what i did was remove input 2 and moved the volume to to that hole, and rewired a mid control in the tone controls by sliding the bass knob where the volume was and placing the mid control where the bass was. this way when used as a combo the only function i lost was the use of input 2, which i never use.
"Tone is in the instruments. Technique in the hands. Do what you will." ~quote from some guy at the TGP forum
"Without a doubt, the quality of your instrument will effect your tone, and any pickups, effects, amps, and microphones used along the way will also have an impact on the sound waves."~Cameron Mizell