1920 Holley carb question

I have a slant six with a 1920 holley carb single barrel. I have idle problems and had the carb rebuilt, but I think the housing is warped because it isn't helping.

We troubleshot further found a vaccuum leak, fixed that, as well as on the distributor the vaccum advance was bad which was also replaced.

When trying to set the carb it won't change because I think something is wrong with the original parts. I don't think a rebuild will work anymore.

Does anyone know if this part would work? It says on the site that it is a reman 1920 replacement, new part number. What else would I need to buy? and will the kickdown linkage fit? Any advise would be steller!

http://www.summitracing.com/parts/HLY-64-3114/