Why not just re-key/re-flat the steeringbox inputshaft?
- Center all steering linkage
- Center steeringbox
- File/grind a new flat on the splined input shaft
- Connect everything


But if the angle of the box is still bad enough to cause alignment issues with the steeringshaft, I would take good pics and get in contact with them to get the box replaced.

The '1st gen' Borgbox (small sector) I bought was spot on with the steering shaft alignment, but it leaked oil on the welds in a corner.

I shot a video of the leak and they offered me a replacement box rightaway.
Being in Europe, shipping back and forth and time wasted I opted to try and fix the leak myself.
I managed to use a simple punch and move some metal to close up the leak.


Having read about others alignments been way off as well, maybe their welding department needs a fresh bunch of people installed.