I just pulled two 3.70 thirds out of an 85 FJ60. The front chunk is mint - and the rear appears tight, with maybe a 1/8th inch of play in the pinion (nothing compared to some of the older 4.10's I've run.
I am willing to sell the ring and pinion from the front and the complete rear third. Make an offer.
I am planning on installing an FJ80 ring and pinion in the front diff - but might part with it complete if the money were right enough to allow me to pick up a complete fine spline 4.11.