Dana 35 C-clip or non C-clip

Is there anyway to tell whether or not your axle has a c-clip or not without opening it up?

the backing plates are different.

looks for 4 half square nuts on the backing plate. That's the retainer plate bolted to it. I don't believe the c-clipped axles have the retainer plate, but no personal experience with a c clipped one.

Your are correct