Was looking through (to respond to another question) the stack of unlabeled pictures I have and I ran across the following picture that illustrates well how much overspray did (in some cases) pass through the back up lamp hole and the end of the hanging rear valance (attached with two or more screws depending on plant) onto the rear cross member and frame. Don't this is specific to any plant or years (could apply to any of them IMHO so thought I would share
Notice
1- The shadow (showing light gray primer) on the taillight panel where the valance was attached
2- Overspray of orange (this was a special paint car - Color of the Rainbow/Month promotion car) on the frame rail and rear cross member
3- While were there - this happens to be a 68 Spring San Jose car so you can make out the dolly mark and the second (further back on the frame rail) dolly mark. That mark was produced by the pad where the Cougar body would ride on the dolly if it was being used for that purpose this time
4- Rest of the rear cross member rusted over the years since it received no or very little primer from below (though it would have been galvanized originally) since the jets would have stopped spraying before they were at the very end of the car to reduce rain down on the current car or the one that followed
Hope this helps some one