Jason Mcc

Just got a 73 Z, low mileage, single owner, very little rust, looks straight from what I could see laying on the ground in the bright sun. Took it home and got it jacked up to remove the old undercoat and hunt down hidden rust and this is what I see Obviously I need to get the straightness checked by a shop but my question for veteran owner / restorers is : have I made a huge mistake?