I'm sure x-gaming has the answer but I can't wait til Monday!

My coin buttons are 5 and 6 (on the top) now so as not to interfere with the pinball side buttons
But now I'd like to add a coin door for appearance. I don't have to hook it up but I might as well but it has to be connected to the side button.
So...then I'd have to make the side buttons the coin buttons. But won't the flipper add a credit then? I don't understand this. Doesn't seem to be a way to have both unless I pull the button out of the hole and swap it with the one on top ('5' default)....or ...just make a different coin button for the pinball...makes it a tad bit confusing. I (the arcade master) know how to use everything though! My friends need an instruction manual haha.