...65-70 pixels wide, and whilst this might under other circumstances be sufficient to make an enhancement, and get an index with 60 to 80 percent accuracy...
So near and yet so far!
I really can't remember the number, so I think I will have to let this drop, unless I spot the car and recognise the driver - stranger things have happened. If I go back to the police with such sketchy (non) information I will be wasting thier time.
Still I have learned a few things along the way - not least of which I always drive with your doors locked...
Thanks everyone.