Sorry guys I assume you are all tired of hearing this same question over and over again. I have read every possible thread and watched every possible video, and I have also been trying to get it in for over 12 hours now. I do not understand now how the smaller side of the sear spring can even engage with the auto safety. It seems like it's too small to possibly engage and stay engaged. I am very mechanically savvy, I rebuild classic cars, can fix just about anything and have built guns but this is by far the most frustrating little spring I have ever encountered. Please help! I'm just done with this thing do any of you think it's just worth it to send it back to cz and have them put the bleep spring in?