[ercoupe-tech] Cowling Bumps

[Donald]

What is the story with the bumps in the cowling?  I had been led to believe 
that the bumps had to be added because of different spark plugs/harness, I know 
my Ercoupe just very recently had them added.  I was surprised therefore to 
notice that serial number one in 1939 had the identical bumps!  What gives with 
the bumps or lack of bumps?