WD40, CRC, RP7 or kerosene. Loosen the nut and turn the bolt slowly as you apply. Work a flat blade screwdriver under the head and lever it up as you turn the bolt. If that doesn't work use the nut to protect the threads on the bolt and tap it out carefully from inside the hull. If that doesn't work cut the head off the bolt and punch it through or cut a slot in the spacer using a cold chisel.
Use Duralac for reassembly.

Darryn
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