to compensate for the angle, you have 3 choices:

drivetrain lift to lessen the angle of the t-case flange

CV driveshaft

degree shims


honestly, the degree shims will probably not get you anywhere near where you need to be, plus to match the backward sloping angle of the t-case flange, you would need to point the pinion to the dirt.

i would go with the CV shaft.

otherwise, deal with it. if your truck is low speed wheeling only, its not a big deal. i have a similar setup but with a single t-case and i run std. u-joints at both ends.

for proper gear break-in, swap the front and rear 3rds