Canopy advice

I'm currently working on. Ju88. I have the night fighter version but I have most of the parts for the bomber version which is what I would like to build. My question involves the rear canopy which is in two pieces.  I masked them and test fitted against the front canopy.  When canopies are in sections like this, do you guys normally glue the sections together and then mask? I'm afraid if I glued them together with the masks on that I might glue the masks to th canopy. Also what kind of glue to you use the glue the sections together.  I have in the past used testors clear glue with little sucess. I've tried Elmers white glue but that doesn't seem to hold real well.  Same goes with micro Krystal Klear Has anyone used Tamiya extra thin glue or testors liquid cement?  I know super glue can fog but has anyone tried slo-zap. What I would like to do is have the canopies on the model and run some kind of cement down the seam.  Any thoughts as to how to do this?  

Thank you