Not specifically for the firebird, but check out the "links" page at www.empeg.com. If you're good with electronics, there's a schematic there for a control stalk interface which will allow any third-party switches to control the Empeg, provided you can get to them and wire them up to this controller box.

But you have to be able to build something from the schematic, and it's not trivial. Perhaps this person will eventually sell kits of this unit?

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Tony Fabris