I am working with the vendor on some other options as he feels it just can't be the booster. I have been tied up at work for the last few weeks so I haven't had a chance to work on it. I want to re-look at the linkage for the third time and make sure there's no preload. I've also tried some other ideas from him like cleaning out the relief holes in the master and bleeding individual calipers to narrow it down before going to the booster, so really anxious to hear if yours gets fixed so I can go down that road if it works.