Good morning all, hoping I can get some of your expert advice. 1968 SS / GTX tribute car with Dana 60 / 3:54 gears, want to change to 4:10's but my mechanic says they will not fit due to the fact that I have a series 2 carrier and I need a series 3 carrier. Now I have never heard of a series 2, is there such an animal? To make matters worse it's also a 23 spline. I would really like to get the 4:10's to work, any suggestions? Thanks!