screws that hold the sight assembly in place are loose...too loose. This pistol has the split washers under the sight assembly. When I tighten them down, the slide binds. Is there a happy medium with this thing? I have seen others, newer I suppose with assemblies that seem more solid and have "spider" washers that appear to sit inside the screw hole on top of the assembly. Can I upgrade to that type sight assembly or maybe an aftermarket with a rail?