PLEASE HELP can any 1 identify this rear end

Hi and thanks winstoninwisc for helping me get my feet wet.
I sent him cell phone pics but our timing has not been the best this weekend.

so here is what I have the dif # is 1634985, and instead of the casting having an "X" on it, there is a 5

the hub ends have a Castle nut that holds the drum on

I have pics of it all, So the big question is...do I do all the hammering that will be needed to get 1/4 key way out to get a look in side of the pig or is it a waste of time as it's an obsolete Axel assembly