Trigger guard - Aero Precision AR-15 Magpul MOE Lower Parts Kit w/No FCG

Kit came with all the necessary lower parts aside from trigger assembly (purchased advanced trigger separate). However, the trigger guard comes with what appears to be an 1/8” screw that you could possibly lose if you are not careful to secure one side and a push pin that doesn’t even fit in a stock AR machined hole. I attempted to attach this Aero lower parts kit on an Aero lower receiver so it should fit seamlessly. Not the case