Mystery vibration at 25 mph can't be diagnosed. It's not the front end!

Man, I stirred up a hornets nest! It's all over now. Conclusion; I correct rake, which has always bothered me ( to much 1970's bling), and then or at same time diagnose if B&T is a culprit with washers. If it is a problem, follow the instructions by slantsixdan to take to a well respected drive line specialist, that welds, and change B&T out. Seems like I can handle that. All I have is time. Thanks everyone. jeffrey356