Hi,
I’ve heard replacing the down pipe/ catalytic converter is a real pain. So getting at that 02 sensor doesn’t look fun either.
My questions are:
1). How rusted in do those bolts get, are they a nightmare or by any luck anti-seized at the factory? ((119,000 miles on car)
2). How long do the stock cats last? I have to replace the back of the exhaust and would rather do the whole thing than have to revisit it in a year or two. (Of course I’d rather just do the back if the cats last 250,000+)
3). Any other things I should be aware of?

Thank you!