Use the watch crystal glue and then use white glue to fill in the other areas around the canopy. The white glue can be smoothed out using a brush dampned with water. Super glue or CA will melt or distort the thin vacuform canopy. I found out the hard way.
Another item you can use is clear epoxy. Mark the area on the fuselage and apply a little epoxy. Let it reach the almost cured state where it is still tacky and then install the canopy. This will prevent damage to the thin plastic of the canopy.
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.