The 9.5" ring gears are much stronger than the 8" but the pinions have same sized shaft and seal so the old course spline units break due to the small minor diameter. The fine spline pinions have a larger minor diameter which is exactly the same as a toy-mini so the flanges are interchangeable.
The 9.5" thirds with fine spline pinions came stock with 2 different ratios. In the late '70s FJ40s at 4.10, in FJ60s at 3.70 and in FJ62s at 4.10 ratios.
If you want to get the whole front axle then the FJ62s are the most desireable IMHO. They have more gusseting and a 10° higher pinion angle for better clearance.
For a centered rear you'll need to build a hybrid using a combination of cruiser and mini bits and pieces.
