Sachtler Adapter 75/100 75mm Ball Base to 100mm Bowl Adapter

My three stars is not for the product's quality itself, but rather, its limited compatibility with other Sachtler products. I have the FSB 8T head with Speed Lock 75 legs. I have a 100mm bowl on my camera cart, so I just need an adapter for when I do builds there, before I switch over to the regular tripod legs. The problem is, when you install this adapter, it will no longer fit on the Speed Lock 75 legs. The knob that comes with this kit is too large to fit on the tripod, and the knob that comes with the FSB 8T head does not have enough threads to tighten all the way when these threads are installed. The only way to switch from 100mm to 75mm is to unscrew the threaded bolt (in the stock photo), and attach the old one that came with the head. Then of course reversing the process when going back to 100mm. This is the second adapter I have purchased to try and solve this problem, and it would seem that the search continues