Okay... straight to the point. At around 1,500 rpm, my shifter handle starts shaking left to right fairly bad, but only at slight to around 3/4 throttle. If I floor it, it stops. If i let off the gas or push in the clutch, it stops. It happens in every single gear, but not in neutral. It doesn't do it all the time, but it's getting worse and much more frequent. I'm not sure if it's a broken cross member, mounts, rear shaft, u-joints, or the inner mechanics, etc... And there are random vibrations throughout the rpm in general, but this is the most prevalent. I've been going through so much mess with this car, but I love it and I want to fix it. I've combed through page after page, and I can't find anything about something like this.... any help?