Yeah those bolts were hard I was afraid they were going to brake, I heated them with Mapp Gas until Cherry red for about 5 minutes, then used my Harbor Freight 1/2" electric impact. Then they finally came off.
Yeah, Chevy has always used inferior hardware on exhaust. It almost always breaks. I recently worked on a 1991 Ford Explorer and managed to get the manifolds unbolted from the pipes without breaking any studs or bolts.
