Yes^^^^^I also recommend taking out the inner wheel well liners in the front and checking the "pocket" at the bottom of the front fender. Dirt will accumulate there and when it gets wet it allows rust to form quicker. I recently learned this on another Ford I have and found a handful of dirt at the bottom of each fender well. My other Ford has a plastic insert that I guess is supposed to keep the dirt out, but it is a '98 so there was 20 years of accumulated dirt. So maybe a handful over 20 years isn't too bad.
when I took my front fenders off to wire speakers, I sanded and painted where the fender meets the rocker, they were rubbed to bare metal by age and vibration. There was some moisture and dirt trapped as well.