Yep. Bolt-in....curious as to why you would need to change an auto pedal for an auto pedal?
Ahh ok, I remember now. You'll probably want to push out the studs on the new pedal assembly, mock it up in the car and mark the holes with a sharpie. Then you can drill and re-install the studs.
Good Idea to get a new pedal box though. It should be easy enough to find one.