Tim,
I'm not explaining myself correctly, which is causing you to work harder than you should.

So to save face I uploaded a photo of the lever in question.
The Lever is outlined in yellow. Check attached
The photo is of the manual carb Throttle Body Assembly, it is hard to see the lever in the auto choke carb illustration.

Looks like there is one Throttle Body Assembly just for 55-56 Passenger car and 54-57 H.T.
Check Grp # 3.729 part # 7007984
I wonder what the difference is in the Body Assembly for the above, Maybe the throttle Lever ?

xfiles
Attachments
Carb throttle lever.jpg (51.55 KB, 63 downloads)