So I have done this in the past. My butterfly opens. However, the linkages for the accelerator and kick down just haven't looked right. In trying this again and leaving the brick on I found the butterfly did open but my carbs mechanical cams weren't actuating the kick down enough. In playing with the cams, springs, and adjusting my kick down linkage I found my accelerator cable is shot. It is stretched or wrong for the car. I Mickey mouse it to take out the slack and then adjusted the kick down linkage.