1960 era clerks used a manual typewriter.
You pushed down on a button, and the letter, attached to an arm, would fly up, strike a ribbon, and “stamp” a letter onto the paper positioned behind the ink soaked ribbon.
The entire assembly would advance, left to right, the same predetermined distance. Each typed letter/number occupied the same amount of room on each line.
Each typewriter was unique. You tie a document back to the typewritter used.
The OP demonstrates that two different typewriters were used to fill out the form. In fact, some demonstrate multiple types of font and spacing.
The Birth Certificate pdf is a fake, and compiled from more than one sample document from the 1960’s
I just don’t understand the manipulated image rlmorel posted. I know there never was a document. Just don’t understand the “p” and “l” comparison.