offset hanger pinion angle problem

I got to comparing parts, and the new shackles are 12" longer than the old ones. also, the offset hangers raise the front eye 1/2" closer to the car.
seems to me this is going to put about 2" less pinion angle in it, but I already checked it before disassembly, and it was 5 degrees, so I used the same angle, but farther inboard, since i'm reusing the same springs

3 degrees is alright for a fast street car, right? i'm figuring it'll run in the high 12s, but will be aspiring for mid 11s sometime in the future....
didn't want to use shims to degree the rear, since the perches are new, and now's when the angle needs to be built in.....

guess I can estimate the height the car normally sits at and lower the bottoms of the springs onto jackstands at the right height. then put the housing on the springs and check it.....