Before we start here, let me say I am brand new to this forum, and to Glocks in general. I am a long gun man and just now got the pistol fever and my Glock 17. So please no trolls telling me I am a stupid noob

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My question has to do with the stock fixed sights on my Glock 17. Can I change them to adjustable night sights, or would my night sights have to be fixed? I asked the guy at my gun shop, but he had no idea either. He ended up trying to get me to buy a rear sight mounted laser lol. That is not a bad idea for intimidation factor, ease of shooting without looking down sights, and such, but right now I am just interested in the night sights. Thanks in advance!