Re: Dislodging Edson pedestal bolts
I had to break the plastic cylinder that held the compass up high, then was able to get the heads loose by turning them with vise grips (abuse, but allows for a lot more torque). My plastic cylinder was UV damaged, so this wasn't a big loss. I replaced my binnacle compass with a smaller surface mounted one (mostly to get the compass farther away from my GPS with it's magnetic SD slot door).
You need to take things apart all the way down below the engine controls to get a tap in there and make them smooth again.
Put it back together with new bolts and lots of Tefgel.
boats that I sail on regularly: Pearson 28-2, Rondar 505, Yankee 30, Blanchard Junior