The first year of production for superposed was 1931. Due to the low number of this example, most agree it is a 1932. It was made before the barrel selector was integrated into the tang safety and the selector can be seen on the lower receiver next to the trigger.
The metal alterations consist of refinishing, coloring and engraving. Angelo Bee is a well respected engraver and has upgraded many superposed guns from grade I with mild to wild upgrades. His engraving is respected among most. The rib is not altered in any way. You can see the little step just forward of the breech in one of the photos.
The wood (I have no idea who did the restocking) never came from Browning like this. Some would say it is contrary to the plain style most grade I guns came from the factory with. But, with a complete refinish, the collector value is pretty much gone.
I found this gun for sale in its current condition and liked it as I am a sporting clays shooter. It performs in that role quite well.
What's left is a mechanically very sound, hand-fitted over/under that balances right on the hinge pin and smokes clay targets.
Regards - redleg