I tried removing them but they would not budge. I tried on 3 separate visits to remove those buggers. The nuts would not budge from under the car.
I finally bought a jack and stands and got my butt under the car and I'll be dammed if I couldn't get the nut off. One of my friends employees, laughed at my little jack and pointed me out to the lift. Once on the lift, things got a little more complicated.
Car up on the lift. It's so light it almost floats!
I still couldn't get the nut off. I briefly gave up and moved to the drivers seat. Looking at them, they had a nut under the nut?!? I quickly realized that the nuts were welded to the car! I quickly removed three of the four nuts on the driver side and the third just spun. I couldn't get at the top of the bolt. Well, it turns out that the seats are definately adjustable, just frozen in place. WD-40 and manhandling shifted the seat enough to get the last bolt out.
I revisited the passenger seat and they did not have a nut under, and the seat wouldn't budge even with WD-40. I got a piece of 2X4 and placed it on the seat frame and started whacking it with a mallet. It finally moved enough to get to the bolts and it was quickly removed.
The driver side seat has one of the hinge pins sheered and will have to be delt with. The passenger side is in good shape, though is missing the two back bolts and the bolt to keep the chrome back release in place. Both have questionable re-upholstery work and likely can be fixed up. The mounting frame on both are rusted and will have to be cleaned, potentially painted, and lubricated.