The launch and testing area is actually a mile or two from the manufacturing area, so the actual fabrication and assembly doesn't get blasted. The only thing being built actively in that area is a new, much beefier launch mount since they're getting ready to start prototype on the Superheavy booster (and also probably tired of having to rebuild the erector-set ones that Starships break on every test, lol)
Meanwhile, on my Mini's bookmarks in Safari, I found this link from 2008 where a lucky dude got the mother of all Space Shuttle behind the scenes tours, LOTS of photos in this thread:
http://forums.pelicanparts.com/off-t...lots-pics.html