Can the axles from a c-clip rearend be removed without taking off the tires? I suspect they can. I have an old truck with a 12 bolt and locking lug nuts and the guy I bought it from lost the key. The universal removing

Yes you should be able to.

As long as the vehicle has drum brakes then yes. If it has disc rears then the wheels need to be removed to get the calipers off- the calipers will help retain the rotors which retains the axles from coming out.

i think i'd just get the lug nuts off one way or another