78 1ton front and rear end

[fla wildman]

I have a 78 chevy 1ton crewcab that was an old gov. truck my father got from and action was told my the 4 wheel shop when he got lock out hubs put on on it that the front and rearend was bigger than most 1tons does this mean it could be a dana 90 have herd of them but did not know if they were better than a 60 or even if it could have one and if so how do I tell this the hubs are bigger than any thing I have seen on 60's