Did the male part slide through the chassis easily mine will not push in?You're missing the lock that secures the stock open. Remove the flush cup from the stock (above the grip) and re-use the flush cup and small screw to screw in the post with the nipple on it. Then screw in the cup that clamps over the nipple on the stock like this. Then when the stock is opened all the way this catches and holds the stock in position.
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