The experienced regulator/voicer has filing skills, regulating chops, voicing tricks, and an array of solutions to apply in response to constraints of piano, time, budget, and the vicissitudes of by-eye referencing. Even for them, variables represent challenges and simpler is better. For the rest of us, simpler is way better.

So. My tools or yours, travel and square hammers to vertical, position the action in the piano for best tone, and level strings to hammers in the piano. This needs to be coordinated with settling the wire throughout its lengths to finish with the fit at pitch and the piano in tune.

I think, whether by serendipity or design, such a configuration between plate and soundboard maximizes stability, resistance to collapse, and sensitivity to energy transfer from the strings. The bearing meets the belly's opposing forces directly, consolidating and balancing resources, creating best resonance, power, and sustain. And best tuning stability.