I have a 73 duster with a 318 and 7 1/4 rear end. I just got a B body rear end from a junk yard that is a 8 3\4 open. I was reading some info that guys are also putting ford 8.8 in dusters also. I was gonna get my B body rear end cut here localy and the guy told me $250. I just looked on craigslist and a guy has a 8.8 ford rear end for $250, and it is a posi!!!! What should I do, if the 8.8 doesn't bolt right up and it extra hassle I will keep looking for a 8 3/4 posi. What do you think?