So a buddy of mine has this old school zues amp that weighs at least 25 pounds. It says 650 watts, but I'm sure it does at least 1000 or 1200. But here's the problem. APPARANTLY There is a little card that goes into the bottom of the amp, that switches it to mono, or another side switches it to stereo, so on, bla bla. Now, he doesn't have said card. NOR can he find one. Unfortunately, I don't have pictures of it. But does anyone know what I'm talking about or does anyone know where to find one ? It's like a 1980s amp. Thank you !