Will the seat back in my '71 GMC K1500 lay forward?

[Clanky]

Hello,
I'm sure this is a simple question, but........ I need access to my fuel tank, I can see 2 large phillips head screws on each side of the seat, I'm assuming if I remove them the seat back will lay forward exposing the fuel tank? My screws are rusted in pretty good, so before I drill and easy 'em out, I want to make sure first that this would give me access to the tank. Or, do I need to remove the seat? I'm just trying to get access to the nuts that hold in the rear cab mount bolts so I can put some liquid wrench on them, I'm replacing my cab mounts this weekend.
Thanks much!
Karl