Just to be clear, you don’t need to disassemble the trigger. Just remove the Barreled Action from the stock & take some close up pictures of both sides of the trigger group. Like below. Actually, you may be able to tell yourself by the picture. Here are a factory, RifleBasix & Timney together. The big tell, is the deletion of the Bar spring in the aftermarket trigger groups. Only the factory pre-Accutrigger uses it, while the others use a standard coiled compression spring.