I will be building a new batch of fixture plates and typically set G54 X & Y at the left back corner and use the part for G54 Z.
The fixture plate will mount multiple aluminum part work pieces that are not surfaced and are raw cut stock with mount holes.
I am wondering if it is a better method to use the fixture plate for G54 Z as well (not the mounted part).

It seems there are advantages to both approaches.
Part G54 Z advantages:
Stock thickness variations is compensated in the Z elevation (first run).
No dedicated G54 Z touch-off location; with limited Tormach travel, maximizing fixture plate usable area is a big advantage.

Fixture plate G54 advantages:
Set G54 XYZ without parts loaded on fixture plate.
Consistent G54 Z for all runs.

Standard G54 methodology is important between all fixture plates; all G54 XYZ should be achieved the same way between fixture plates.
So if a few fixture plates require maximum real estate usage, then it seems the G54 Z on part is the best solution to standardize G54.

How do you approach this dilemma?

-Uman