Based on my experience do not spend time and money on rebuilding 3 speeds tranny. Swap it with 4 speed original Toyota FJ60 or FJ80. 2F will be much more to enjoy with 4 speed transmission.
If I was going to go through restore process all over again, I would do two things.
1) Without spending a dime on 2F, I would swap it with 1KZ or 13BT, 3B.
A carburetor engine technology (2F) is 30 years old and no need to rebuild. Just swap it you will be much happier in the end.
2) 5 Speed must be mated with diesel engine of your choice, along with tubes (Bell housing) followed by Power Steering, disc brakes to avoid redundancy.