Just went to pick up my Mk1 from the bodyshop, they re-painted the bonnet and rear quarter panel, and was gutted to see that the new paint is a different shade of blue. I wasn't expecting a perfect match because obviously paint ages and fades etc but the new blue is way off. The bodyshop guy said that they'd taken the fuel cap off to get the colour matched in the computer but it still looks wrong to my eye, especially when the sun hits it.

So my question is this, did Renault definitely produce different shades of 449?

I read this thread which seems to suggest they did.
http://williamsclio.co.uk/forum/showthread.php?1593

If so, is there any way of finding out which shade was used to paint my Williams originally?

It will end up costing me yet more money but I'd rather have it done right.