There are a lot of discrepancies or shall we say, bum information in the manual. It says that the piston and nut should be removed as part of the cleaning process. The cleaning is discussed as above, and not needed. It also says that all muzzle worn carbines are to be counterbored to get to good rifling. How many are? 2% maybe? It also says that every carbine with any visual obstruction to reading the serial# has to have the number duplicated at the front of the receiver. how many really are? 10% maybe? Also the safety has to be changed to the rotary type yet there are thousands of late ones that skipped that part. They'll have a type 3 band and type 2-3 sight but the push safety is still in place.