I would recommend installing solid state relays to handle the halogens, just to be safe. There is nothing quite like blasting down an unlit section of the freeway in the middle of no where, at 70, in the middle of the night, and having all your lights go out. "Coffee? We don't need no stinkin' coffee! We're wide awake now." Especially since they come back on after a bit and then go out again, on an increasingly frequent basis.
Steve