Trim as necessary for a flush fit. People like myself with rather large beer guts have to make shims unfortunately. On the 3 rivets, I would recommend using nylon webbing so that material stays put. It'll act as a hinge and you enter the armor from the opposite side. Ukswrath, a SWAT member here, sells a fans, brackets, and any electronic you can think of. He's got quite a bit of my paychecks in the past year lol.