Help! New Carburetor????!

I am still not being able to clamp throttle cable on the metal collar. Still @ 1" from collar. I think it's because of adapter plate I had to use. It added some on height.
Also looks like I will be needing rear kick down bracket like JohnnyDart's, and my slider bar is too long. Someone had cut & welded in 2 places. Does anyone sell the slider & brackets for this application? When I install everything the kick down will not let the carb go to full throttle.
Looks like I have old 273 version of the back bracket and will need to go to the style in the first pictures in the green car??? Any Advise??