40/41 LZ Radio

My 40 Zephyr has a 41 radio plate in it and I wondered if I should restore it as a 41 radio or replace it with a 40 (if I ever found one!) I don't think the car was shipped with a radio based on the build sheet I got from the Ford Archives. It was shipped in March of 1940 so I guess that was getting towards the end of the model year. Maybe the dealer put the radio in later and by that time the style was changed to the 41 radio. At any rate, your thoughts on this would be welcome.