Topic: Apron Markings on Dearborn Car

[Jondors]

I spent some time today stripping undercoating/sound deadener from my outer engine compartment aprons.
 
I found these markings (44, 21, 01 or maybe 420, 411) on the left apron. 

They appear to have been written on the panel after the panel was painted.
 
Are there any published or community defined meaning to these numbers?

My car is a Dec 65 built, Dearborn GT Fastback.

The apron is stamped 12-2

[J_Speegle]

Thanks for sharing. Have found very similar ones on 64-65 Dearborn built cars. Don't always have to be located on the same inner fender panel or only on one side so keep looking