There are numbers cast into the throttle body. I can't see them on your images. Please tell me what they are and we can move toward solving the mystery. I'm away for a while and don't have my Carter notes, but working only from memory I think the 235 carburetor should show 788 and the 216 should show 630. If an incorrect throttle body was put on a 2100s I'm sad to say you may have a "frankencarburetor" made by somebody who had a 2100s float bowl, possibly a matching air horn and a 216 throttle body. A couple of years ago I bought a couple of Carter YF models which suffered broken throttle body flanges (either from being dropped or tossed I suspect) and had a great deal of difficulty finding parts carburetors. I think I have a throttle body which might work for you, however it is on a complete carburetor (with manual choke) made for the 230 Chevy.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end