How can I fix the perspex display panel in my car?

Their web site suggests this...

"For glass, clear plastic or painted surfaces, dilute 1 oz. in one gallon of water." which suggests it's strong stuff.

My guess is that chemicals in the cleaner have melted the surface of the clear plastic and have permanently damaged it. You might try lots of hard rubbing with a metal polish or auto body finish restorer (basically the same stuff). Their abrasive qualities may polish out the damage but it will likely take ages.

Good luck...

Peccavi
August 2009