Lower mount bolts frozen

I'm replacing steering the shafts on a pair of 1991 130TLRPs'.
I got one engine apart, fixed and put back together. But now on the second one, I can't get the bolts out of the lower mounts. These are the big bolts that attach to the sides with rubber mounts and go through the lower mount housing at the bottom of the steering arm. (54 on this page's diagram - Yamaha Outboard Parts 1991 130TLRP BRACKET 1 Diagram )

The nuts came off the bolts easily. But the bolts are solid in the mount housing and mounts too. Everything else is off the motor.

Any tricks? I've been spraying with PB for over a week. A BFH only mushrooms the bolt. I'm planning on using a torch to heat it up today. I also was thinking about grinding opposite sides of the threads flat and trying to twist with a whrench. I could sawsall through the mounts to get the bolts cut but I'm trying to spare the mounts ($100).

That's all I got.

[tunnels]

I'm replacing steering the shafts on a pair of 1991 130TLRPs'.
I got one engine apart, fixed and put back together. But now on the second one, I can't get the bolts out of the lower mounts. These are the big bolts that attach to the sides with rubber mounts and go through the lower mount housing at the bottom of the steering arm. (54 on this page's diagram - Yamaha Outboard Parts 1991 130TLRP BRACKET 1 Diagram )

The nuts came off the bolts easily. But the bolts are solid in the mount housing and mounts too. Everything else is off the motor.

Any tricks? I've been spraying with PB for over a week. A BFH only mushrooms the bolt. I'm planning on using a torch to heat it up today. I also was thinking about grinding opposite sides of the threads flat and trying to twist with a whrench. I could sawsall through the mounts to get the bolts cut but I'm trying to spare the mounts ($100).

That's all I got.

I would guess it crystilized salt !!!! acts like the best loctite you can buy . Heat is about all there is unless someone else has and suggestions , Remember the aluminum parts have a low melting point and wont stand to much heat !!!!
I do hope when you are reassembling that you are greasing everything, nuts , bolts , holes that bolts go through etc etc .

Heat...heat...heat

Well I got them out... kinda. I used a propane torch, heated, heated and heated some more. Then hit the visible bolt portions with FreezeOff. Then smacked the end of the bolt with a BFH enough times to get it to move about 1/4 inch. Then I sawzalled that bolt between the mount and the lower mount housing (the other never budged). With one mount off the other can stay on the housing until I take it to a press. Then I should be able to push out the bolts.

And yes EVERYTHING is getting liberal amounts of antisieze. All bolts and holes are being cleaned up with tap and die (is that spelled right? hmmm too early). I'm trying my best to avoid these issues in the future.

Thanks...