The elevator pushrods cannot be installed upside down.
The purpose of the the Elevator Power Off Test is to see how many turns of the Stabiliser Trim Wheels it takes to trim the aircraft, from memory its about 2.5 turns, any more than that then adjustments have to be made.
These procedures are written in the AMM and also in the DDG.
I don’t think I said “up side down”, looks more like “installed wrong”, to me. At any rate, they didn’t explain the whole procedure to me, just what I had to do. And I didn’t have the AMM in front of me, just the yoke. I was a new hire, probationary F/O, fresh out of the military, and generally pretty used to doing what I was told. Within reason.