One option is to build your own two button foot switch. This will give you channel switching and effect loop switching OR reverb and master switching, depending on which rear jack you plug into. I had made one for a Mesa Lonestar and it works with my Renegade. I used a small alumnim box to save space on my pedal board. If you are interested I can point you in the right direction on how to make one. It's a very simple circuit.
Or you can buy a Mesa compatible foot switch. Actually this type of switching is used by a lot of amps so many will work (fender, peavey) or can be modded to work. The Egnater foot switch has two of these circuits built in, and two TRS type cables going through the foot switch cord back to the amp. That's why it has two plugs and two jacks for foot switching.
The thing I haven't tried to figure out is how the slider switches work to select clean/lead/both for the four switching options. I would need to open it up, and it's tighly put together so I've not tried it yet. Might be using resistors or perhaps diodes.
Hope this helps.
