Jeff that is correct they are splash shields and the blue paint was under the sound deadener and under a coat of black paint. I also found that same paint method on the number brackets and front frame rails.
Not certain what your referring to as the "number brackets"
So you found it on the front frame rails under the red oxide layer?
but definitely the first layer of paint on most of the interior front end metal
Without either (all of us) of us knowing the history of the car this sort of discussion is difficult.
There are some possibilities but many would not fit if this or that did not take place in the past.
The area covered by the blue seems large and out of sequence for a factory application but for a repaint after stripping the car down to metal in some sections of the car its possible its a result of that. Did the bottom of the front frame rails show a nice red oxide color with drips before you stripped it?
Seeing your pictures of the front end there is no going back and checking some of the details at this point.