Hi, so my top right rear bumper bolt is stuck/rounded. Does anyone have a good solution to getting it out? I have tried welding a socket to it but it is too rusty and i cant get up there with anything to clean it(my hand is barely able to squeeze up and touch it.).

To be clear the bolt in question is the one above the exhaust pipe.
I got all the other off, the two on the bottom just broke off and the top left was easy enough to turn. Im not too happy about driving around with just the two top bolts in place. - I dont want to end up bending some mount or anything...

Thanks

 

Penetrating oil - heat - weld a bolt to it - bigggg breaker bar