Whoa whoa whoa whoaaaa.... HOLD THE PHONE!
Are you kidding me? This actually works?! I'm in the same boat dude, I'm actually the guy who made the thread you linked to describing the problem. I never found a solution to this and went back to an older mouse.
I'm gonna need some more details on this, a lot more, as I have next to no knowledge of how circuit boards work.
so I have taken the zowie apart and simply switched the top circuit board around
What do you mean you just turned it around? What would that even do? Just physically turned it around? What??? Haha, are you a wizard?
I see that's a Zowie FK in your picture, not an AM. And I also saw that this guy in this video says the FK can have both sides buttons enabled at the same time. He says it here: https://www.youtube.com/watch?v=rYxNJi3QqV0#t=7m5s
However, I have yet to confirm with him if that is truly the case.
Did your trick work because of whatever you did to the circuit board, or simply because the Zowie FK allows both side buttons to work at the same time, or is that guy in the video wrong?
Either way, if possible, can you elaborate more on what you did to achieve this? I would be super nervous doing this myself, but I'm extremely tempted to try it if given some more details/tutorial.