I assume the carpeting on the floor is going to come out..
Cut the carpeting around the bolt heads and remove it..
Then spray all around the bolt heads with the pb blaster again liberally..
Allow to penetrate( again) for an hour or so.
Put a box end wrench on the bolt head...Exert some med pressure as if to loosen while you rap the bolt top-wrench with a small hammer..several times.
Then put the socket wrench on an see IF they will loosen..
NOTE:
ONCE they DO start to come loose a BIT, STOP and spray some MORE PB Blaster on the now exposed bolt threads below the bolt head.
Take your time and be patient..Bolts have been in there 35 years and they sorta got used to being there..:)
Even with the age and mlileage of your car, old bolts that enter old steel captive nuts can be frozen up a bit.
They'll come out..just gotta think and be patient..Jim
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