Help vibrations

[Peter]

I am having a big problem with vibrations, I think it comes from the driveshaft or something in this area. I have tried the following.
Pinion angel set up and down are now at front 2 degree down, rear axel 2.5 degree down and driveshaft 1 degree down rear.
The driveshaft has been fully balanced and is straight and with new u-joint. I have tried two different complete rearaksel carrier.
The vibration is coming at around 4000 RPM in high gear (TH700 with lock up) and getting worse when I goes higher in RPM. The rear is 3,89-1. and the car is a 69 Camaro take a look at http://www.pro-touring.dk

Thanks Peter