[DeltaMustang65]

Oh crap. I can't quite tell what the first picture is showing, but the bottom one is bad news. I'd go very easy on the car or that leaf spring may pop right out. I honestly don't know how they'd fix that kind of rust damage, even for 5K, so I'd be very skeptical if I were you. Hopefully someone else here can give you more of an idea about what to do with the car, since I've never had a problem like yours before.

Almost forgot, welcome to MustangWorks. If you've got pictures of the car, you should make a user ride page and put the link in your signature like some of us do.