the bottom. Anywhere there were dings (there were only a few), we went down to metal & used a stud welder dent puller to pull the ding out. We got them out mostly with that, & then smoothed them out with a little Bondo. But there isn't hardly any Bondo anywhere on the car. This was a California car when I bought it 8 yrs ago, so the wasn't any corrosion anywhere. As far as time, it took probably 120 hours, maybe more, to dismantle the car & do the paint prep.