Glad you were able to figure it out. P for a Z ??
This is from our reference doc for a GE T6 Fanuc control.
Making offsets in the "X" axis
1. Press the "offset" button.
2. Press "cursor up" or "cursor down" until the cursor is under the tool number you want to change.
3. Press the "U" button.
4. Key in the "amount of the offset".
5. Press the "Input" button.
6. Press the "program" button to return to the program.
Making offsets in the "Z" axis
1. Press the "offset" button.
2. Press "cursor up" or "cursor down" until the cursor is under the tool number you want to change.
3. Press the "W" button.
4. Key in the "amount of the offset".
5. Press the "Input" button.
6. Press the "program" button to return to the program.