Nothing says you can't run two switches - one for the front and one for the rear BUT they should both be able to be activated simultaneously from one location. Most are achieving this using cables but I'm sure there are many ways to skin this cat.
Stainless I'm surprised to hear that your battery was intact after your wreck. I did not see the extent of your accident although I heard it was pretty bad and that you were lucky to have gotten away with what you did, but, the majority of accidents I've responded to have the batteries launched very far from where the car winds up.
Shorts, sparks, and shocks are all good concern but I think a higher priority is getting engines and fuel pumps shut down.