2001 Hunter 340 Rudder (fiberglass post)removal troubles

[Bronxite]

I need assistance with removing a rudder ( fiberglass post) from a 2001 Hunter 340.
The post head has a split quadrant (as a clamp on the post) , held with 4 clamp bolts and a center thru bolt for the emergency tiller. The 4 clamp bolts came out no problem, quadrant halves are loose, but the 3/8" SS through bolt for the emerg. tiller, is impossible to even budge. It seems to be epoxied into the fiberglass post. Nut and washers come off, but the bolt wont turn for nothing, tried every penetrant oil, impact driver, 6 point sockets, pipe wrench with extension, nothing budges this 3/8" stainless steel bolt. I'm afraid to break off the bolt head and then I'm in real trouble.
Any suggestions?

 

[Don S/V ILLusion]

That's what happens when someone uses a SS bolt in an aluminum part (the quadrant).

Option 1: heat
2: drill it out.

 

[Bronxite]

Thanks Don,
Thought of those too... afraid any heat gun or torch hot enough to get the alum. quad to expand, might surely melt the composite rudder post as well.
Drill it out ? To do this one would have to demolish the entire quadrant as the thru bolt threaded tip is set into a pocket of the quad. and not accessible to drill. The bolt head might be accessible be but it is locked at 45 Degree angle inside the floor opening by the binnacle stops and you cant line up a drill. To do this the entire binnacle would have to be removed as well.

I think I'll try a moderate heat first.

Then price a new binnacle from Edson, if they make them anymore.

 

[Crazy Dave Condon]

Not sure if taking a punch and tapping it a few times to see if it would move first if corroded. It has been a long time since working on one as a former dealer. I am afflicted with CRS.