Technical A strange shoebox part

I picked this up at a swap meet last year. Never seen one before so I thought I would throw it out to the wisdom of the Hamb. Its an aftermarket gas filler door for 50-51 Ford. Its cast metal and has the letters GEM 525 1950 Ford on the back. Anyone seen these before?

 

After market part from the 50's (?). I seem to remember similar if not the same at "Top Auto" in Tacoma, WA back in that time frame.

 

GEM did cast some stuff.....most I remember from early 60's go-kart racing days.....

 

I went to look at some cars and there was a '49 more door Ford that had about every doo dad screwed to it, probably all of JCWhitneys catalog..Real gow job; the only thing missing was one of them doors..Saw that emblem somewheres recently, got brain fade though..

 

Has anyone seen this in an aftermarket catalog? Im trying to get a time period. Im thinking sometime in the 50s.

 

could it be from mercury meteor ?

 

It looks aftermarket to me,but I have never seen one before.Gonna use it for sure!