At 6'3 in still getting eye watering "wind-whip" sitting down, As you can imagine standing is even worst! does anyone make a nice looking windshield extension?

Get a good pair of goggles when you are running fast! The windshield is useless!

Only thing I would try is those bolt on , flip up wind deflectorsI don't think you will find per say a windshield extension for the Scarab. I usually run with a good pair of Harley Glasses with vents on the sides and there wrap arounds.

Good luck!!