I think maybe he means to use a later factory choke cap which uses a 6 volt feed from the stator terminal of the alternator. If that is the case, it can't be done without using a power resistor. What carburetor are you wanting to use, tooponies?
I don't know where the elect. choke kit came from but it was on a autolite 4100 4 V that I'm running on my mildly built 289 in my 64 1/2 convertible that has a generator. I know about the stator terminal on the alt. but don't know where to hok it up o the generator.
The stud on the back of the ignition switch is likely the best place. If it were me I'd prefer to use a relay drawing power from the battery and just use the ignition switch terminal as a "trigger". Chokes don't draw a bunch of power but I'm just not fond of loading up the back of the switch to draw additional power through the aging factory harness.