Hi one possible way is to use VERY fine abrasive past first I would recomend Tooth Past ( NO JOKE )
It will of course depend on the depth of scoring your screen has suffered
you can also try Bluebell or similar liquid metal polish, last resort try T Cut
always polish in a circular motion overlapping the area by a couple of inches ( sorry 25 to 50 cm ) the job requires elbow grease NOT heavy pressure, it is not a quick fix they dont exsist
If all else fails and taking it the vehicle is insured you could check with your insurance company to see if you are covered for Screen damage as a repair does not involve you in any access or effect you no claims but sadly this screen service is normaly reserved for fully comprehensive cover only,
The other alternative is to contact a screen replacement company for a quote if you decide to do this I can recomend
Budget Windscreens you could be pleasantly supprised
Best of Luck
Roger L in Essex, June 2004