That's one of the things that I've wondered about. The factories design the drivelines with specific dimensions, angles, etc & folks regularly add shims and such. In your case, Valkman, raising the front of the engine 1/2" would seem to call for maybe just 1/4th" at the tranny mount. That would bring the driveline angles back to NEARLY what the engineers called for, I think.
What I have NO grasp of is just how critical are the angles, anyway??? I'd hate to have the front U-joint blow up in a hundred, or a thousand, or 10 thousand miles. Maybe worse than that would be driving around gritting my teeth, worried that I had prepared my driveline for an early death and set myself up for the legendary "pole vault of doom"
BC