the Boss 9 I am restoring at the moment had a screw mounting the line, next to the original holes, three of them. No plug like shown, but had some sealer pressed into the holes. So something was going on.
Armond, if you don't mind, when was that car assembled? Just to see if it lines up with the ones/time period I have
Sorry about my misinterpretation of your comment Jeff, I guess my question still is as first asked what where the two holes intended for, as their diameter is 5/16" and the screws are only 1/4" I measured these with a Vernier and they are definitely not designed for the screws. Am I hearing that some floor pans had these holes and some did not??
Every floor I have pictures of have at least the single holes and since they are there when the second mounting holes are there would suggest that they were made in the floor panel when it was made or there would have been no reason to add them later. The size of your mounting screw and the size of the unused hole to me supports the idea that this was a hardware size issue. The screws they had for the task at specific times didn't work in the original formed holes so they had to make new ones
Is this an early design for something that was deleted but the holes where punched anyway?
Not apparently just an early thing as we have at least one other period later in the year when Dearborn had the same problem again and addressed the same way - except without the plugs that time
Great discussion, I am surprised this topic has not come up before and my car is the only one so far with rubber plugs in the holes.
Consider that fewer 70's were built compared to many prior years and in turn less of them being restored compared to other years. Just look at the number of posts for different year on this site.
