No need to shoot for perfection, reasonably level is fine. Our galley and fridge are midship and we place level on floor in front of fridge. Upon arrival we level TT side to side and chocks wheels, then level front to back using tongue jack.
If rain is in the forecast we may tilt TT to improve water runoff, as long as it is comfortable to walk around in our rig we know we are close enough for fridge to operate properly. We are going on our 8th year camping with our Dometic fridge and it continues to perform flawlessly.