The three buttons at the top of each control section are MODE, BACK & START.
The MODE button toggles the digital/analog funtion.
That controller already uses actual arcade parts, so no hacking is necessary. If you want better sticks or buttons, you just replace the ones that are there with better ones. It is an extremely easy process.
The most work you may have to do is extending some wires.
[EDIT]
Thanks for the compliments guys. I can't really take all that much credit though. I pretty much copied the original controllers layout, and black paint and plexi was a pretty basic choice to go with.
