WOW!!

[Hammer Gun]

The mystery goes on! The TPS and SER Bk have different descriptions of the gun

[Charlie Price]

6966 is a D6 listed in TPS as a gun for the 1876 show -- see Chapter on Show Guns. The lists of show guns came from special lists that Parker kept, not the stock books or order books (as I recall). Maybe 6966 started life as a lower grade and was recorded as such in the stock book (source of the Serialization data). A study of data in the stock book and order books may help explain. I have never seen a Parker sidelock with such steps.
Charlie Price

[Autumn Daze]

I stand corrected. Thanks everyone for the clarification.

[Pa SxS]

It's the real deal. It was made for the 1876 centennial and is so noted in the stock book. It's one of 5 D6"s sold to the Parker Bros store in NY for $300 along with other lesser grade guns for the centennial. There is a notation for each of these guns being for the centennial in the stock book.

It's a 12ga, 28" barrels, 7 1/2lbs, 14 1/4" pull, full choked, pistol grip.