Use a carpenter level to get the coach as level as you want both side to side and front to back using your jack system.You can place the level on the ceiling or floor or counter.
Then adjust the rotating bubble device to center the bubble levels front to back and side to side. Tighten any lock down screws on the bubble device. Once it is calibrated that way, you can refer to it while setting your jacks up next time.
2003 34' Dolphin 5342, W22, UP, UPGBrake, F and R Track Bars, Rear IPD sway bar, Koni FSDs, Safe-T-Plus, Scan Gauge II.. 2004 Jeep Liberty, Blue-Ox Adventa..