Buck' Sterling Range Turkey cook Time

[Chemman]

So I have this old Bucks Sterling Range in my living room when I purchased my house in Heeney Colorado 15 years ago. I only used it a handful of times up until I retired this year. It has turned into our main heat source in our top floor and finished basement house on the shoreline of Green Mountain Reservoir. Story my wife and I were told is it came from back East with the Heeney School teacher 1900-1940. Appears to be in very nice condition and mostly complete. We have used it to heat for the last 2 months and it is currently ready to run us out, produces a lot of heat in "Bake" lever setting and seems to use slightly less wood. I just pulled out dinner for tonight, Chicken and Dumplings. Seemed appropriate since we just got 5 inches of powder snow. I have only used it to cook twice, enchiladas and this dish. On Bake and a hot fire box produces about 400F oven and cracken hot stove-top. There is a rotary air vent in the exhaust stove pipe and I have not figured out what closed and open seem to do. Other than the "Bake" lever and the vent in the exhaust don't see alot of adjustments to control temperatures and burn rate.

I can use any help anyone has to offer. I would like to cook a 20 pound turkey in the range, anyone have cooking instructions for this fine turn of the century stove?

TIA

Chuck