Windshield hinge bolts won't come loose

i am going to have to look into those, thanks for the suggestion!
For heating a bolt like the ones in the windshield frame, try to keep the keep the heat centered on the bolt head with as fine a flame as you can like the one shown in the image on the package.
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For heating a bolt like the ones in the windshield frame, try to keep the keep the heat centered on the bolt head with as fine a flame as you can like the one shown in the image on the package.
View attachment 119333
s this to keep the "damage" to the paint and surrounding area to a minimum or purely just the way to use a torch like that. Will the heat discolor, mess up the surrounding paint?
 
Even here in Oregon (with no rust) mine were a pain in the ass to get out.

One of them I actually had to get out with a screw extractor. I replaced them with stainless steel bolts and used plenty of anti-seize.
aside from the work involved getting it out was it hard to remove without scarring the paint?