There is a small rod that acts to push the safety back when the top lever is moved to the right. The rod is removed when the Hunter One Trigger is installed because it won't fit otherwise. If your field grade 12 (assuming it has double triggers) doesnt automatically move, its probably because someone removed the rod at some time. Taking the stock off LC Smith's, and especially putting it back on, is a more complicated process than a Parker or a Fox.
Try to find a gunsmith who has done it a few times. Or, just get used to a manual safety.
