Yes, they did drill holes in the bumper. You could see about 1/4" of bumper from the edge of the screw head, and the holes on the bumper support are very close the the back edge of the support. That pretty much puts the bumper even with the back of the support, without hanging over the back much if at all.
My car is pretty low, but I haven't scraped it yet since painting. I busted it up pretty good when it was on the 89, and I was trying to get used to it. I hit it twice, both times was on grass, in pretty deep drops. Once I got used to it, I learned to be very careful with it. Here is a picture of how it looked before repair and paint. It is in grass on a pretty flat tire for this picture though. If you look closely, that molding is crooked, it lines up well with the body molding on the door like it should. It's lined up right in the sig picture after paint, just under the molding line.