What it is somewhat remarquable is that the F2, F3 and G airframes were almost identical. It was somewhat a matter of swapping a 2-men cockpit for a single seater, or replace the swept wing by VG. By all accounts, one F2, one G, and 2 F3 were build or almost build, four airframes. To be a fly on the wall at Dassault in 1965-68 and watch these four airframes evolve into different aircraft...
A similar thing had happened a decade earlier. When you think about it, by 1957 the Super Mystère B2 and the prototypes Mirage III-01 and Etendard IV (all flown in 1955-1956) shared the same Atar 101G turbojet (the Etendard having a 101E - a 101G without the reheat). In turn the rear fuselage (lets call it the "Atar rump" ) was somewhat common to all three aircraft. Which then differed by
- the intake: frontal on the SMB-2, side-mounted on the Etendard and Mirage, the later having "mices" inside for supersonic flight
- the wing: swept wing for the SMB-2 and Etendard IV, a delta for the Mirage III
This is kind of unique in aviation history or at least the jet age - AFAIK. Same engine (101E / 101G) same rear fuselage, mated to different intakes and wings. Kind of modular fighter.
If one bought a SMB-2, an Etendard IV and a Mirage III 1/72 scale models, it would be possible to create hybrids - a tailed or no-tail delta SMB-2 or a supersonic Etendard with "mices" and reheat from the Mirage III. or a swept wing Mirage III.. wait, that's the F1, it had the Mirage V fuselage.
edit: Deleted one of my earlier post as unuseful.