Well it turns out there is not a good way to mount the brightness switch.
I will be turning in to "full brightness and burying the strip into the frame as per advice from Shmups forum.
It has a piece of paper that covers an adhesive section. Remove the paper to reveal the adhesive and simply adhere this to the inner-top of the shell.
Seal up the unit and tap on that section of the shell to increase/decrease the brightness. It is a very nice feature.
Here is a demonstration of how it is placed. Not my video but I have done the same procedure on my NGPC and couldn't be happier.