Body Numbers

["John Di Fede"<difejo@consumer.org>]

     My 1975 TR-6, CF36442U, has two number plates  above the right side 
     footwell on the firewall.  Is this normal?  If so what is their 
     significance?  I don't have the numbers right now, but thought that 
     having two plates was a bit unusual.
     
     Also, there is a number on a tab connected to the windshield frame on 
     the drivers side.  I don't believe it matches the commission number on 
     the left hand door jamb. Should it?  
     
     John Di Fede
     Hopewell Jct. NY.
     
     75 TR-6
     73 MGB
     80 MGB (project for sale)