Jerry, the OP is not saying that "you don't know nuthin", he's gently presenting his information, and he's right. Take it easy.
The driveshaft angle is relevant for calculating the angles of each U-joint, and that's how the OP is using it, so saying it's irrelevant isn't helping.
I wouldn't rotate the pinion down, that will increase the angles at both ends, which won't be good for the U-joints. I tried that, and while I was able to match the pinion and tailshaft angles fairly well, both U-joints were working at over 10° and I had vibes.
Instead, I would either lower the skid plate, or better, add a motor mount lift (MML). That will lower the tailshaft, reducing the angle of both U-joints, especially the front one. Lowering the skid with washers is a cheap way to find out if changing that angle will fix your problem. Either way, though, you may have to mess with your shifter if it bumps into the rear of the tunnel hole or the boot bezel.