Ah! This is one of the problems I had with my car on both sides! I adjusted them by extending the slots in exactly the same direction line as they were already following. Both sides were different in that one side the gap was narrower at the bottom and the other at the top. if the gap is narrower at the bottom and wider at the top you need to extend the front slot of the side screen until you get the front edge of the side screen parallel to the A pillar of the screen. and the rear slot if the gap is narrowest at the top of the side screen.
Mine were way out and if the gap difference is greater than 5mm top or bottom then like mine its probable because the screen A pillars are incorrectly positioned. For this you will need to ease the dash out of the way, fairly simple and if you look at my lower screen to scuttle seal replacement post I have described the procedure for this operation. The screen or A pillars are simply secured by three fixings per side to the scuttle and you can easily access them with the dash out of the way. Loosen both sides with the side screens off (ease of access) and then carefully after refitting the side screens position the A pillars in their best position in respect of the gaps to the side screens and hand tighten the fixings on both sides. Best gap is somewhere between 5mm-12 mm. Chances are you will still not be parallel but the adjustments to the slots will be a lot less after this approximation. When you are happy sequentially tighten the A pillars to the scuttle carefully and check they remain in position. They do not need tightening like you are mooring the Titanic to them!
I expect both procedures may be needed as I don't think they ever get really well fitted at the factory and their tolerance's are somewhere in the ball park of "that's close enough"! But getting this shut line right really does improve the look of the car!
