66, 6 cyl, 3 spd.
The carb I have on the car is an Autolite 1100. The tag says C6OF-AD. From I can find this is for a 67, F100. I believe I should have a C5FO-(something) 1 of 4 models. That being said, what is the difference between what I have and what I should have? Jets, venturi, etc..?

 

The C means 60's and the 6 means '66, you have the right one, but it will probably work on a '67 F100.

 

it was common for FORD to interchange parts. DIY had ashow, restoring an old 66 fastback. theydid a great example: under the center cap of the steering wheel on old mustangs, you'll find FALCON embossed. C6 is correct repr. 60 and 6, D is for 70, etc, etc.