For the C engines. What i'm saying is if you went with the E motors, which by nature have higher thrust because of super high RPMS, you can put the side by side rather than inline and increase thrust, because 2 or 3 of the Lumeniers in the E kits and 5" or 4" triblades, respectively, would fit into that duct. I would still strongly recommend if you were going to do a DH mossie, go with props. There are a handful of aircraft that go well with that kind of ED-faux system, any kind of aircraft with a pronounced high-bypass turbofan engine. This includes:
The a-10
S-3 viking
Harrier(maybe, not as a VTOL)
transport aircraft with modern engine configurations (C-17, C-5, an-225, An-72)
Any commercial airliner that's been produced since the 80s
The importance here is that pure jet engines rely on exhaust gases expanding for propulsion. Because of this, the inlet and outlet are relatively tiny, and trying to fit an EDF that suits this would wind up with either an undersized EDF or an EDF choked off from airflow. High bypass engines, like those on the A-10, rely on the first stage compressor blowing a bunch of air past the pure jet engine, which gives much better performance at low altitude for rapid takeoffs and low altitude maneuvers, while the actual jet core provides enough power for a high speed cruise. its kind of a nice tradeoff between turboprops, which have good efficiency and performance at low altitude with very limited high altitude applications, and pure jets, which have anemic static thrust and do better in terms of efficiency at high altitude
Also of note, i probably would not use that type of airframe for a ducted fan anyways. Its much like the Me-262, in that the engine slings so far below the wing that any attempt to land would result in a nearly 100% chance of destroying the EDF unless it is well-protected and reinforced. As i am finding out, landing gear on large aircraft are a pain in terms of structural design.