The dreaded 'Q' plate

A lot of kitcars in the UK have a dreaded 'Q' plate which indicates that the exact date of manufacture was not recorded when it was first registered. This can have a detrimental effect on the vehicle's value although I am not really sure why it should. It probably has more to do with number plate snobbery than anything else. I would like to reregister my car with a conventional plate to give it a more authentic 30's look but have been told by Swansea that I need confirmation from the manufacturer of the date that the body/chassis unit was manufactured . However, the original invoice/delivery note is not regarded as sufficient. I don't have details of the donor registration as I have failed to trace the original builder and the kit manufacturers Carisma Engineering of Sandy, Beds ceased trading many years ago.

Has anyone got any bright suggestions or do I just have to live with it?

Andy