TopFlite DC-3/C-47 questions
Perfect fit.
Definitely not underpowered.
Not overpowered either- you can achieve scale flight between 1/2 - 2/3 throttle.
I honestly don't know about altitude effects for these engines, but just based on the air density ratio, I don't think your power fall-off will be too much (which applies to all engines).
- George
P.S.
I spent a little time in Billings and Colstrip, Montana- some of the prettiest scenery I have ever seen.