Like Cass said in 1968 they finally smartened up and made the two piece side gears one piece. I know b/c I had one that the spiders and side gears were chewed up. When I bought the rebuild kit they were the one piece ones as well. But if you have the two piece and the splines are not aligned, take the axle shafts loosen the bolts on the carrier and turn until they (both axles) drop in fully and retorque the carrier bolts.