RE: Senior header tank
I wouldn't go over 12 ounces without going with a pressurized/regulated fuel system, such as a Cline or the other brand, which is safely tucked away in my brain, but which will not surface to the fore so that I can type it for all to see. Ah, I remember, the name is Iron Bay.
Some folks have even used a Walbro carb's fuel pump and regulator function to accomplish the same trick. With such a large, light weight model as the Kadet Senior, the small additional weight of the Walbro carb will be negligible, but you would be hard pressed to find a better pump and regulator. Some of the folks on this forum have mentioned the fact that they did hijack a Walbro carb in this manner for use with glow fuel. Anyone?
With the Walbro set up, your 40 oz. tank would work, but I would look into baffling the innards so that your model doesn't suddenly find itself very tail heavy when you raise the nose to climb. Good luck.
Ed Cregger