I am making a custom case and have cut the opening for the PSU with screw tabs for mounting. I have a CX750M PSU but the screws that came with it are far to short. I have the right type of screw (6-32 UNC) but after passing through the wall of the case there is 15mm left over. is this OK to pass in to a casing of the PSU I do not want to hit anything in side. Can not open the PSU to check as the is a warranty seal over one of the screw holes.