Removing '73 Seahorse 4hp gear case bolts

[rchad26]

I'm trying to remove the bolts from my '73 seahorse...impossible, even after lubricating w/ PB Blaster...suggestions? Unfortunately, I already snapped one off

 

[rchad26]

Forgot to say, gearcase bolts

 

[racerone]

Small propane torch and heat the area where the bolt screws in.---------Usually that will release the bolts.-------I assume a salt water motor.