How much weight gain from adding a Dana and roll cage.

the dana 60 from a 67 to 72 ford 1/2 ton pickup is the lighest . compared to 8 3/4 is 35 heavier. a dana 60 is a dana 60. the main housing has different wgts. 1/2 ton ford , then B& C mopars, 3/4 ton pickups, then 1 ton pickups, lighest to heaviest. just foor for thought.