I took my calipers off and the top bolts did not budge at all pulling on them. A 3 lb. sledge hammer on a breaker bar did the trick. I did not have to deal with salt water dribbling into the well near the bolt however.
How to bust a bolt loose with a sledge and a breaker bar: Get the socket wrench (six point or Allen in my case) well engaged on the bolt. Load the breaker bar as much as you can with one hand. Strike the end of the breaker bar with the hammer. Loading the breaker bar before striking is imperative, as is using a heavy hammer. Using a sixteen ounce carpenter hammer, or striking an unloaded breaker bar is wasting your time.