steering wheel - alignment

The thing is it should not be done this way, master spline or no, because the steering box actually has a "center point" in the gearing. If you don't have an (old, etc) OEM wheel to use for a test dummy, you should do whatever you need to in order to line up the master spline

ESPECIALLY if it's a power assisted box. They "search" for center when the pump is energized. So, if the toe is adjusted so the steering wheel is off center, that can cause a pull one way or the other.