Up until today I thought my car was virtually rust free.  Today I pulled up the floor mats from under the old seats in anticipation of installing my new seats soon (more on this later).  Under the mat on the passenger side I found a significant rust hole

The driver’s side has a much smaller hole in the same location.

I’m worried that the seat rail puts considerable stress on that area and could fail, especially on the passenger side.  I think I should fix this before putting the new carpet in.  Stay tuned.