CIEDX3

ok I have soaked the bolts that go into the frame for several days with pb blaster, tried to break them loose today and the only thing that broke was the head of the bolt rung off, I twisted the head of a 1/2" drive extention and have broke several 18mm sockets trying to get these bolts out. I have tried a 1/2" impact as well as a 3 foot long cheater bar on the end of a 1/2" breaker bar and have had no luck at all breaking these bolts loose. any advise would be great. oh and the car is a 94 Z28, replacing stock kmember with a bmr big block kmember
thanks,
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