Why dick around with either and run the 70, its a 10.5" ring gear and has the same outer dimensions as a 60. I found one that has 1/2" thick 3.5" diameter tubes that weighed 58# when cut down to size. The 9" pinion is smaller than a dana 44, it only has a 3rd bearing to reduce flex. Nines are just puny compared to a real axle..Tim

1941 Taylorcraft
1968 Charger
1994 Wrangler
1998 Wrangler
2008 Kia Rio
2017 Jetta

I didn't do 4 years and 9 months of Graduate School to be called Mister!