How tight are these bolts supposed to be? As tight as can be gotten by hand on the wingnuts? Should one use a pliers at all? The bolts I removed had rubber washer/sleeve combinations which resembled little high hats? The new bolting has rubber washers only. Is one better? P.S. Ive already had the shockingly cold experience coupled with a pit in the stomach experienced by cranking down too much and cracking the china (big chunk and 4 gallons of water instantly on the floor plus what spewed from the cold water supply before I could shut it off?