So I just bought a new three position trigger and I am wanting to drop it into a lower that unfortunately has that damn little stop to prevent the selector from rotating 180 degrees. Does anyone have any advice on how to best remove it? I can't see this being a major project, but I'm willing to be that I do not have the proper tools/setup to not make it look like crap. Should I just take it to a machine shop and have them grind it down? It's a KAC ambi lower, so I'm trying to make sure it stays in the best condition possible.

Thanks in advance.

Probably cheaper to find another lower without the stops or to grind them off of yourself. Then you could preserve your original lower intact.

Setting up in a mill would be the most precise, but finding someone to do it might end up being difficult and expensive. Kind of a sticky area performing machining operations on a lower right now, especially for a non-ffl machine shop.

Is the stop on the lower itself or does the selector only have two positions?