Rear end gear swap help!!

[Awann99]

I’m running a stock 3:07 open rear in my truck with my th350. Since I am swapping to a 700r4 those gears will not work well with that transmission for a number of reasons. I have a spare 3:73 72 12 bolt and a unknown posi 77 12 bolt (both 5 lug). Would I be able to just have a shop swap the gears or is the 3:07 a different carrier and I would need to swap the whole rear end to get the gears I want. Thanks guys.