The X-location of the fuselage CG are given as follows,
distances are given as a fraction of the fuselage length:
Single Engine Tractors: 0.32- 0.35
Single Engine Pusher: 0.45 - 0.48
Propeller Driven Twins: 0.38 - 0.40 (tractors on wing)
Propeller Driven Twins: 0.50 - 0.53 (pushers on wing)
Jet Transports: 0.42 - 0.45 (wing mounted engines)
Jet Transports: 0.47 - 0.50 (rear fuselage mounted engines)
Fighters: 0.45 (engines buried in the fuselage)
Note : Do not count the propeller spinner in fuselage or nacelle length!