For all slant-6 applications with 1bbl carb from 1960 through 1972, the kit number is 1231.
1973 and later 1bbl carbs take a #1234.
"Super Six" 2bbl setups take a #1232.
The source is
CarbsOnly.
...
The round black housing contains the thermostatic spring, and you can see it has two electrical terminals on it. The spring and housing are attached to the mounting bracket by a retainer ring and screw. By loosening this screw, the housing can be rotated relative to the bracket through several whole revolutions, giving essentially infinite control over the initial spring/rod tension. The housing has a notch on it and the bracket has calibrated lines to help you keep track of your adjustment. As shipped, the unit was NOT adjusted (no rod tension); I had to loosen the clampscrew and rotate the housing until tension developed in the pushrod. Not a big deal, just something to keep in mind.
You can see how the bracket attaches to the exhaust manifold in the same manner as the original choke. Other variants of the slant-6 choke kits have slightly different bracket fixing (2 holes instead of a bolt hole and a tab). This 2bbl kit has the pushrod with correct length and bends to connect to the factory type 2bbl installation.
The black-and-copper device on the left side of the photos, in the middle of the bundle of wires, is the heat sensor. You mount this in a location that "sees" engine heat and provides a good ground via the copper mounting strap. This device senses engine heat and regulates power to the heating element inside the round black spring housing. The wires provided are nice and long, so you can experiment with different locations in the engine bay to find the one that gives you the right choke come-off rate. A good starting point is one of the threaded bolt holes in the top surface of the head. If the choke comes off too quickly in that location, you can move it elsewhere.
The 1945 carb was introduced in the 1973 model year, so the 1234 kit will work on your truck using a 1945 carb.