I am wanting to switch out sights on 3 pistols (to night sights): Kahr P380 Kahr CW45 SA XDM9 I am handy, but don't have a sight-changing tool. I have looked at the P500 Universal Sight Tool, but it is $130. Should I get the sight tool and do my own sights? Or should I just have a smith do them? How do I make sure they are centered? Do I take the tool to the range and make adjustments in response to point of impact? I hear those Kahrs are bears. And the CW has kind of a funky front sight.