My recent book review of One Second After got a lot of comments and the book is based on the aftermath of an EMP attack on the U.S. Serendipitously the fellas at American Partisan have a couple of good articles about EMP attacks and Faraday cages.
More handy information that you maybe should think about taking advantage of. Tensions with China are at the highest point I can recall and they are one of the few powers with the ability to do this. I doubt they would as we are their biggest customer but in a desperate move? Maybe.
I have wondered about EMP's and their effect on Automobiles.
Would it be possible to pound a good grounding rod into the ground, and attach it to the car frame to ground the car and route all of the pulse from the body to ground, thereby avoiding pulse damage to the electronics? Would not help while driving, but could make a difference when parked.
If the body is what catches the pulse, could giving a path to ground avoid damage?
And what does it take to "harden" electronics? Could that be done by an amateur?
Those are questions way beyond my expertise, the second link has a video from a guy who seems to know a lot about this topic and he might have answered those questions