No, a 4 cyl carrier cannot be installed into a V6 diff casting.
4 cyl carrier;
Cone LM603049 45.2 mm
Cup LM603014 79.9 mm
V6 carrier
Cone X32010X 50.0 mm
Cup Y32010Y 80.0 mm
Therefor, you need a bearing: 45.2mm (1.25/32") x 80.0 mm. This combination is not available.
Years ago, ARB made the first Turbo, V6 air locker by pressing sleeves onto the small diameter 4 cyl carrier, and then OD grinding them to 50.0 mm.
This is the only way that I have ever seen this done.
That's a lot of work to put a weaker, smaller carrier into the V6 housing.
Marlin
thanks again Marlin. I want to buy a detroit locker but i have a 4 cyl third in my runner right now but later on when i want to upgrade to a v6 third and lower gears i want to be able to use the detroit in that as well. It sounds like that is possible if i buy a v6 detroit and buy the special bearings to put it in my 4 cyl third.