Everything ossiblue said plus the front suspension pan. Poke around the T-bar mounting points. Even if it looks solid, poke it with the ice pick. The torsion bars attach to the low point of the suspension pan where moisture collects.
Don't be caught by surprise like I was. These areas looked completely intact ("looked" being the key word there) when I bought this car...the pictures are 6 months later and that time was spent in a dry heated garage. The damage was MUCH worse than the pictures show.
Also, if there's any undercoating that looks different from the surrounding area or new, poke around in that too.
Good luck...keep us posted and take pictures!