Add to the above list rear window gutters, bottom of cowl/firewall joint, upper part of toe pan, rocker panels, convertible side reinforcements where floor meets inner quarter, front mount area for rear springs, subframe mount areas on floor pans, core support (bolt on), rear window channels, front window channels (especially on a car that originally had a vinyl roof). Also look for stress cracks in the left rear quarter at the corner of the window in coupes, and the front of the roof at the right windshield pillar.