Technically, it will bolt in but the 70 is a bit wider than your 65's rear. I don't know how much wider, approx 2" IIRC, there have peen posting about r/e sizes with an accompanying chart. Try a search because I cannot recall that web location.
The 70 rear is 2 inches wider making the wheels stick out 1 inch farther on each side. It will work fine with the right wheels. The drive shaft may need to be shortened depending on which yoke is on the rear end.