Corroded Nut Driving Me Crazy (photos) - Please Help!

[Scott J.]

I purchased a new faucet for the kitchen sink yesterday. But I the nut that holds in the old faucet is severely rusted/corroded. After spending six hours on a precious Sunday with no luck, I'm asking the brilliant minds of you BPers for help.

First of all, the pictures don't do it justice. The nut is about a third of an inch thick, making it very difficult to grab with the basin wrench. But even when you can do it, me and two friends couldn't get it to budge an inch. Also, it's in a very difficult location with only a few inches of room on each side of it.

This is what I tried:

1) Lots of WD-40, with plenty of time to soak-in
2) Blow torch - the old heat & cool method didn't do a thing
3) Lots and lots of elbow grease. I must have put all of my might into this thing 30 times.

I can think of two other options:

1) Cut it out- this may work, but the lack of room and the metal everywhere makes it risky.
2) Cut out the old faucet from above. I'm hesitant to do this because if it doesn't work I won't have any faucet.

Thoughts?