Hiya razorback1 and thx much for your thread. Others might know for sure, but I believe just the dovetail cut hold it. But either part with 90 bucks to get a sight pusher,or stop by a LGS that has a smith that usually will let you use one for free while there. I franky don't like my rear sight off center axis,kinda not feng shui to me. What did your cz test target look like? Are you a lefty or righty? I've thought I had rear sight alignment issues,asked a range officer at the range,who's never shot my gun,and reassessed the matter when he leaves a tattered hole in the bully at the same distance.
Two common reasons are when shooting right handed,squeezing to hard with your left i.e. support hand. To tight a squeeze makes the barrel shift to the left. The other is that darn trigger finger. Back to basics, using only the pad of the finger and pulling straight back, only letting up till you feel the trigger reset,and repeat. If your finger extends to far over then your finger acts like a hook causing your finger to pull the trigger to the right,sliding the barrel to the left. And hook us up with a few pics of how it went when you sort it out,please and thx. Be well.