I actually bolted the engine in for the first time since the planking was finished. As can be seen, it is a bit of a tight fit in places. If one were building a D3a as an all out scale effort I think you could effectively hide a rear intake, rear exhaust engine. For those into electric power,i think a D3a would make a great candidate. One could make the dummy engine and upper cowl removable as a piece to allow easy access to a battery compartment and the cheek scoops would help with airflow around the motor and batteries.
My main problem is going to be the carburetor mount. As can be seen the carb spacer is right up against the upper longeron. I was pleasantly surprised that it is possible to shoehorn the engine in with the engine mount bolted on and without having to pull the flywheel. I will have to cut a fairly enormous notch in the side of the fuselage to clear the carburetor. You can see in the bottom picture that the engine doesn't appear to be centered. That is because even with the carb off, there isn't quite enough room for the engine to square up. When all is said and done the engine will end up with a degree or two of right thrust. One upside is that the carburetor will at least be partly covered by the scale exhaust.
