Driveline angle help!

[Low Elco]

I've built a 70 swb with a 72 burb rear and sb/700r4 combo. We have a severe vibe between 58-63 mph and a little in other speeds. Seeing as it was built with all stock stuff and only lowered in the rear with a 3" spring, I assumed the driveline angles were fine. Judging from research and leveling the frame this weekend and measuring, that ain't so. Measured off the rear trans face, with /\ being the directions of tilt, I am / 5 deg. The driveshaft is / 5 deg, and the yoke face is / 5-6 deg. This is telling me I am running in a straight line, which I'm gathering ain't good. I am willing to fix this, but I wanna be sure I'm right. Im going to shim the trans up so I'm / 1 deg, and shim the rear so it is / 1 deg, which should put me in the guidelines of 1-3 deg down at the trans face and parallel to that at the rear. Shaft is rebuilt and balanced, ujoints are new. Am I nuts? Is the correct track? Any help is appreciated.