Help with my 1940 Mercury coupe
 

I need some help! I have a 1940 mercury coupe with clear title. I think it was made during the transition period between 1939 and 1940. Nothing done to the car. But it has a 1939 dash, wheels , taillights, floor shift , no side window vent. The car runs and drives but would to know if there os any way to tell and if the factory made it that way is it worth more or less. Thanks for any help. Kenny