Video said:
I think they're wanting it to have both A and B firebuttons.
Funny thing, I was looking at a picture showing how to wire the firebuttons for a 7800 controller, and the way it was drawn, looked like in order to use a 7800 controller on the 2600, you pushed both buttons. I don't know, maybe it was just confusing or something.
Actually, I was the one that started the topic

, and yes, I was talking about both firebuttons. But by what kepone said, I thought he might not know you can at least use it on 2600, so I thought I'd make sure he knew.
The modification is more complicated than I thought it would be, I thought all it would be was soldering a wire to a different spot or something small like that.