Some time ago I purchased a used 10 PC in 223, no box or manuals, I am in the process of working up some loads and decided to take it apart to see if it had the action is bedded. I can't get it apart. I removed the screw in front of the clip release, I also removed the screw at the rear of the trigger guard which just goes into the stock. But nothing moves there is another screw behind the magazine but I can't get to it, I assume the trigger guard and the magazine box are two separate pieces? Does one have to come out first?