Weatherstrip Sealing

[fantasygoat]

One thing that is eluding me on my car is getting proper sealing of the windows and doors.



I've put on reproduction weatherstripping but no matter what I do, the windows never properly seal. There's always gaps, or in the case of my driver's window, in order to get a seal I have to have the window at an angle where I have to push it out with my fingers while rolling it up.

Is there some secret to this that I'm missing?