I know that this is an old thread, but I was thinking about the same thing since I was setting up a smaller than normal size control panel because I am building a bar/counter top cabinet. I opted to go for a dual joystick set up and I had qualms about a top fire button especially since I am right handed and the right hand joystick would be the one I would be using for most games. I was going to put an 8way-4way switchable stick in that position. The other stick could very well be a standard 8 way. With both sticks in 8 way mode, I could very well realize the possibility of playing many double joystick games. However, for these games I usually rest my hands atop each stick...so a fire button there would be a no no. So I didn't want to rule out the tank games and thus the thought had occurred to me to wire in a temporary footswitch to use with the bartop cabinet and use that as a fire button.
Apparently after reading this thread, I am not alone in that idea. I had tried to do some research on tanks to see if there was ever one that use a foot control to fire the main gun. I know that in many fictional movies, Star Wars in particular, there was use of a rail gun that had a foot switch trigger. (I will let you Star Wars fans guess which film). The use of a footswitch WOULD allow me to rest my hands atop the joysticks as that is how I have grown accustomed to working a game with two joysticks in the first place.
So I am wondering if someone actually did implement this concept and if so, how well did it work?
Thanx,
Geo