Well, yours looks a little different than my EMPI 32/36 DFEV, likely because of your fancy fuel line intake. Mine's just rubber hose with a clamp.
On mine, that port you point to just has a hose that goes to the top of the charcoal canister.
As for the electric choke, it just requires 12v that is only is hot with ignition. Under that yellow cap is a bimetalic coil that expand/contracts with temp. You can twist the cap with affects the coil position. It should be set so that when the engine is stone cold that the choke butterfly valves are almost (but not fully) closed in the carb throat-- some use a credit card thickness as an acceptable gap. Once the 12v line is hot (e.g. with ignition on), it will gradually cause the butterfly valves to open. They should be fully open within about a minute or so and stay that way during operation.
Check out how it works with the lunchbox air filter off first. It can be a pain to get at those screws when the carb is in place because the hard brake lines off the master cylinder can get in the way, but you'll get the hang of it.
Hope this helps!
Cheers,
phaetn
1974 CS1
32/36 DFEV; CompuTronix ign.
9.8:1 c/r; 40/80 intake cam w/ Isky springs
Vicks' SS header & adj. cam pulleys
A/R's progressive coils, Koni Yellow dampers
205/50-15s on CD-66 style rims
Momo wheel, Corbeau seats w/ 5 pt belt
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