Alright,
Re: my before-mentioned vibration....it's not the driveshaft. I also took care of the header issue (rubbing on the steering box), and replaced the transmission mount.....and it still vibrates. The wheels and tires (15X7 rallyes w/ firestone wide ovals) have all been balanced. My next step is to balance the drums. I'm at a loss. Help! Also, re: the four-wheel drum brakes on my car.....yeah, they're not the most ideal way to stop, but, I replaced the master cylinder, all of the lines, and had a shop correctly adjust the brakes and I think they work great. Thanks for all of your help!!!