10 bolt or 12 bolt

[caspear78]

ok yall, heres another one for ya, been thinkin about this for a bit, i know i should know the answer to this just by takein my rear end cover off and looking, but im asking here first, what come stock in a 70 1/2 ton 2 wheel drive, in the rear end that is, is a 10 bolt or a 12 bolt that is in it, im thinkin about changeing out the gears becuase it runs to high on the road for me, even running at about 55 it still seems a bit high, im pretty sure that some one has changed it out before i got it, but im just wonderin what is stock in it, that way i can go from there, and then when i pull the cover, i will see which way they tryed to go with the truck,,,,,,thanks in advanced,,,,,,,mark