Okay, home from holiday and got my notes. The only thing I have written down is that most or all of the 2 hole pistol grip caps we've seen date from 1952'ish. Your rifle is a 99F from 1955, so that's odd. Wonder if the buttstock was swapped later on? If you're curious, pull the buttplate and look for extra holes drilled in the end to make it a featherweight. It should also have stamped codes on the buttplate, buttstock and forearm that match.
It's also very possible that my notes aren't complete, or that you have a "odd duck". The sling studs aren't original either, though they are a handy little addon for hunting.
Just to clarify a bit on the 1899 versus 99.. Savage's first commercial lever actions came out in 1895 and were known as Savage 1895's. In 1899 they came out with an updated version, and that stayed as the 1899 until the nomenclature changed to be Savage 99 in 1920/1921. Many models had no hardware or stamping changes when they went from a 1899 to a 99, Savage just started calling them a new model name and logging them in the ledgers as the new models. Other models were discontinued, and some new models appeared.
The original model 1899F was a solid frame saddle ring carbine made from 1899 to 1920. The first model 99F was a takedown featherweight rifle with shotgun buttplate made from 1920 thru 1940. The second model 99F was a featherweight solid frame rifle made from 1955 through sometime in the 70's, characterized by a Model 99F stamped on the barrel.
