You might be in luck. The critical angle for reflections is 30-40 degrees to the surface - Brewster's Angle. Not 90 degs to the sun, which is for blue skies.
Polarisers can be good for motorsport, especially tin-tops as the angle is usually about right for killing reflections on windscreens (laminated) so you can see the driver. They can do funny things to toughened glass and Perspex though.
Check out Hoya HD. It's a very high quality filter and also uses a slightly lighter polarising material, so you only lose 1.2 stops instead of 1.7-1.9 or so.