Paul if you read some of the threads by Jason Harrison you will see that it takes time and money for the research from the Cody Museum. They would have to go through all the ledgers to find out such information and they do it an an hourly rate. I think that only 6,600+ Specialty Grades were made. Double triggers and extractors with full/full chokes would have been standard from the factory, but you could order anything within reason for a price. If your shotgun serial numbers from 171,416-173,371, they made 1,955 of all grades, with the Field Grade being the most common.