GPS isn't the only way to navigate. Given how small Israel is, inertial navigation is probably good enough to cover the last leg of the trip.
Even without that, they could still rely on cameras and old fashion navigation.
Isn't that scarier? They'll need to bomb everything and anything to damage their target. They can't be precise/surgical about it.
The warheads available to the craft in the first wave are basically large hand grenades. It's bad, I'm not suggesting otherwise, but it's not exactly carpet bombing either.
Very unlikely that Iran uses GPS.
All the different services then?
Or just the American one?