Place a machinist's level (Starrett 98-6) on top of the piston cap, rotating the cap, and adjusting the feet until level.
Adjust the bubble level so the bubble is centered.
Final Adjustment of Bubble Level
1. Tighten the SHC screws to slightly compress the belleville spring.
2. Adjust the SHC screws to center the bubble of the bubble level within the red circle.
3. Tighten the set screws to immobilize the bubble level.
4. Verify that the bubble remains centered after tightening the set screws. The set screws can be used to make small movements of the bubble. If the bubble does not remain centered, loosen the set screws and SHC screws and repeat steps 2 through 4