I got a spray tin of Tetrosyl waxoil stuff and sprayed it on the foam insert between the windscreen and bulk head. I smoothed it off with my finger. I used a flat screw driver to spread it along the top and bottom edge of the foam behind the windscreen bracket things. I also made sure to do the foam at the sides. The stuff repells water so it stops it getting in along the top or bottom of the foam.
Alternatively you could remove the windscreen bracket covers and run a length of heavy duty black top the width of the windsceen wrapping it around the sides. If one edge of the tape is fitted flush to the front bottom edge of the windscreen drain channel then you can smooth it back and cover the foam, then trim the bottom edge just below the bottom of the foam. The tape will just look like the foam it is covering. Once again the tape will prevent water getting in either above or below the foam. Refit the brackets.

