65 Barracuda 8 3/4 Rear help

I just picked up an very nice complete 8 3/4 rear out of and 65 cuda very cheap. It has the 741 pumpkin 3.23 gear. I plan on going threw it being was junk yard buy. I have few questions first this should work in my 67 Cuda right? Also what should I do as far as axle seals and bearings? Would it be worth it to put posi in 741 case or get 742? I am going to use this in small block conversion. I am doing to my 67 Cuda nothing really wild maybe a 318 or 340(if can be found).