I sold commercial printing & coding/printing equipment for a few years...
A silk screen would be a terribly inefficient way to linearly code something.
The <span style="font-weight: bold">Packard TVR Suppression 1Q73</span> was in all likely hood done in line while the wire was being manufactured, with a rotary letter press, (rubber stamp on a wheel which is inked with either an anilox roller, or some inking system)
The cylinder indications were also done with a rubber stamp (probably not rotary and most likely while the individual wire sets were being put together) although the impression pressure was much higher as indicated by the "halo's around the numbers" where the paint/ink squeezed out.
__________________
~JAG~
NCRS#65120
68 GTO HO 4 spd Alpine Blue /Parchment 2 owner car
#21783 71 Corvette LT1 45k miles Orig paint - Brandshatch Green - National Top Flight - last known 71 LT1 built.
71 Corvette LT1 42k miles Original paint - Black - black leather - only black LT1 known to exist.
NUMEROUS Lemans blue Camaros,
Monza Red and Daytona Yellow Corvettes
& a Chevelle or two...
Survivors, restored cars, & other photos
https://picasaweb.google.com/lh/myphotos