Originally posted by RogueJSK:
Pretty good deal.
Just note that after installing your new G19 slide on your G23 frame, you'll still have a .40 ejector in your G23 frame.
This should still work fine most of the time, and is just fine for a range gun. But if you want it to be 100% reliable and completely converted into a G19, you'll also want to snag a G19 trigger housing, which will have the 9mm ejector.
Assuming your Glock is a Gen 3 (which is what that slide is designed for), you'd want Glock factory part SP00322, which is the Gen 3 9mm trigger housing with included ejector. It'll run you ~$10-$15. The rest of your existing G23 trigger parts (trigger spring, connector, trigger and bar) will swap over directly into that housing. And there are tons of good tutorials online for removing/swapping/reinstalling Glock trigger groups, which will be a breeze for an experienced gunsmith like you. No fancy tools needed, other than a 3/32 punch.