When I removed all of my undercoat, I too was surprised at the total absence of rust. I did not, however have any bare surfaces. Maybe they took an early cappuccino break when they were painting yours and forgot to finish some spots!
One thing that I was also pleased about (and a good reason to strip all that crap off) is to find that there had never been any accident repairs either.I never tried starter fluid before, but it sounds more expensive than laquer thinner (even though I only used a few cups).
Here's mine "almost" clean...
