The carb on my 28 is a C-RAKX-O
Thought it was original..?
When I last worked on it several years ago I couldn't adjust it how I wanted, it ran, but not as well as it should have. I asked around and looked for parts and found it was very very expensive to work on, supposedly to get it apart some parts will almost certainly break, and they were quite expensive.
Shortly after that I found some modern replacements that looked OK, not exactly original, and were pretty cheap, but I haven't bought or tried one.
I'm supposed to bring it out later this summer for a local car show, they want an old "barn fresh" car. When I got it about 7 years ago it was barn fresh from the mid 60's, now it's "barn re-freshened" for 4 or 5 years..
Curious to hear what you learn about carbs, as I'll probably have to deal with mine in a few months.
Grigg