73’ was the first year electrically heated choke springs were used for most engine carburetor combinations. The intent was to get the choke off quicker than engine heat alone could for the sake of meeting emission requirements of the day. If the choke spring pictured is correct for your application, the pic clearly shows it having a heating element, then a choke control was installed on your car originally (usually under a intake manifold bolt head, on the passenger side near the choke well). Unlike modern day aftermarket electric chokes, those heating elements draw close to 2 amps while in operation and was only required during the first 5-10 minutes of cold start, after which crossover heat keeps the spring relaxed. 2 amps added to the ignition run circuit, including the bulkhead connector and ignition switch. As mentioned, there were a couple different versions, with and without a by-pass resistor, and was later superseded to a solid state design around 77’ or so and continued on through to the end of carbureted engines.
I believe Nacho’s point was if you go without the controller (don’t power up the heating element and crossover is open) there will be sufficient heat to open the choke, just later than originally designed.
