A couple of months ago I bought a Glock 23. It made me realize how gritty my Glock 35's trigger felt. I watched a couple of instructional videos on fully disassembling the glock so I could see if cleaning the trigger and housing and all that would make a difference. I have always heard of "polishing" the trigger and stuff like that. So my question is: What part do I "polish" and with what? Or is polishing for rifles and a better trigger for a glock is just about installing a 3.5lb connector or something of the sort?