Holley bracketry has a lot to do with what transmission you are using, and as you note they do not affix to the intake like Edelbrock, but on the rear "ear" of the carb.
I am not an expert but I just went through this a month ago with my very first Holley, so I will just share what I bought for mine that seems to work: for my 600 cfm with a 700r4, below. I am not saying these are the parts you need. I will say that my attempt to cheap out and make my own throttle stud ended in failure and I ended up buying the Holley part... it has to be the most money I have paid per ounce for a bolt in my life. But, it worked, and with the correct parts there was no slop or slack anywhere and it works like a charm. Unless someone has swapped your original throttle cable with another at some point I think you just have to find the correct part for your application.
https://www.amazon.ca/Holley-20-95-T...111472&sr=8-10
https://www.amazon.ca/Holley-20-121-...00CMDVA2&psc=1
https://www.amazon.ca/Holley-20-38-T...0029JE38&psc=1