Flash Point without the Deck Gun?
This is just off the top of my head, but if the issue you're having is that someone needs to be 'stuck' there, then how about giving everyone a special action to skip their whole turn to "radio the driver" to take the action.  This way, effectively, any player can be it without having to be in the truck, and people can take turns.   Try it out, and if it makes the game easier use the game's built in difficulty modification to re-adjust it harder.