If you are doubtful of the bolts, soak them fir a few days, the get a small portable torch about the size of little propane ones you use for soldering plumbing, but many places offer a 2 bottle set up that mixes2 gases and is ideal for home use.
Heat the crap out of them and then try and gently take them while the are hot.
Cover the surrounding area with wet rags, keep water or fire extinguisher handy just to be safe.
If you take your time you should be. Able to get it all out and not break the studs.
Once you do get it off I recommend you clean the threads well and use alot of anti seize
Good luck!
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