Josh, very sorry to hear about your cancer. You're in our prayers.
In the Shay book published a couple of years after this model hit the market, the author says to remove the gear from the drive train closest to the cylinders, instead of trying to cut the teeth out. I've done this to 3 of the kits, I've built for others and I still have one to build for myself.
The extra gears in the kit, if they are plastic, chances are they are the original kit gears, with a set of NWSL gears currently in the model. The guy you got it from did say it had been upgraded.
Keep it Between the Rails!
SER & NMRA lifer
Josh, sorry to here about that, I'll keep you in my prayers.
In the description it said it was put together by a "skilled modeler",and some things make that statement appear correct, like the cab, tank, and truck bottoms not being glued down so they can be removed for maintenance and lubrication. So that being said, along with the extra gears, makes me think that the gears have indeed been upgraded. I am considering the possibility of just removing, not butchering, the two inboard truck gears that are close to the cylinders.
This is all on the back burner though as I am in the process of acquiring materiel's and space for my new layout, which will be focused on the hills above Soledad,Ca. in the early 1900's and will have a lumber mill, Ranches for livestock, excursion trains to the Palisades(pinnacles ntl momnt), the hill/mining town of Rootville, the Mellville iron mines, and the Syar Quarry on Stonewall cyn road. along with the oil pipe line and pump house that ran north to Monterrey, and a connection to the S.P. spur-line that ran there and into Soledad.
Soledad Lumber & Coal Co.