Decided to finally start building my first AR-15. Got the parts, found a good video and in no time at all ran into my first snag. I have and FDR-15 receiver set from F-1 Firearms. There is already a pin inserted where I place the bolt catch. It appears to be threaded and so screwed in. I can't get it out. There doesn't appear to be any screwdriver slot. At the other end, if it is meant for an allen wrench, it is for one smaller tha 1/16th inch because that won't fit. The threads make be reluctant to go trying to punch it out without some advice. Any tips guys? Thanks in advance.