What part needed the customization? I'm having travel getting mine done, I've also got a ghost evo elite I customized previously to my glock oem trigger. I've started to customize it with this but I'm wondering if there are any other parts I need to shave down.A friend of mine just put this in his gen 4 g19. It required a little bit of work to make it fit even though it says its a drop in part. It feels just like the factory trigger except the pretravel and overtravel are fully adjustable.