I used it on the 1/48 scale Monogram F-4C/D. It took a lot of filling, sanding and time to get it to fit properly. I did not try it on a Hasagawa kit but if it was made for that kit, it would fit better than on the Monogram kit.
Berny
Phormer Phantom Phixer 
On the bench
TF-102A Delta Dagger, 32nd FIS, 54-1370, 1/48 scale. Monogram Pro Modeler with C&H conversion.
Revell F-4E Phantom II 33rd TFW, 58th TFS, 69-260, 1/32 scale.
Tamiya F-4D Phantom II, 13th TFS, 66-8711, 1/32 scale. F-4 Phantom Group Build.