I am currently building a MAME cab from a Dynamo cabinet, and I've filled in the old holes on the control panel and it's time to drill new holes. I want to go with this layout from slagcoin:

which is all well and good. But what I am struggling with is where do I actually put this template on the panel? If I draw a line down the middle then I have P1 and P2 space laid out. But where do I position the template within those spaces? I guess all I really need to know is where the joystick goes. Then the template takes care of the rest.
Is there a standard? Like, 2" from the edge and centered between the top and the bottom? Any good rule of thumb?
Getting the panel to this point was a lot of work and I already screwed it up once. I don't want to do it again.
Also...I assume this template will work for IL buttons? Even though it's meant for 30mm sanwa? I just put the center hole in the same spot but use my 1 1/8" hole saw?