741 v 742 v 489 housings

Ok, thanks to all for the information. I don't know a whole lot about rearends. I definitely know more now. It seems either I change axles to sbp, or change backing plates to the larger size, thats 11in x 2.5 shoes. I'm only out the $18 I paid for the smaller plates. Inexpensive lesson. I may end up selling the smaller plates for what I paid. I'll have to wait and see. Again, thanks to all for the info and the patience.